CN109689394B

CN109689394B - Information display medium and manufacturing method related thereto

Info

Publication number: CN109689394B
Application number: CN201780054343.8A
Authority: CN
Inventors: 香田祖光; 笼谷彰人; 户田敏贵
Original assignee: Toppan Printing Co Ltd
Current assignee: Toppan Inc
Priority date: 2016-09-05
Filing date: 2017-09-04
Publication date: 2021-02-12
Anticipated expiration: 2037-09-04
Also published as: EP3508350A4; JPWO2018043749A1; US11584151B2; JP2022082555A; CN109689394A; WO2018043749A1; KR102398830B1; US20230115123A1; JP7383235B2; US11951760B2; JP2022000349A; AU2017321840A1; JP7036017B2; KR20190050977A; AU2017321840B2; US20210300106A1; JP7294380B2; EP3508350A1

Abstract

Provided is an information display medium capable of improving an anti-counterfeit effect. An information display medium (100) is provided with a light reflection layer (20) made of metal or metal oxide on a part or all of one surface of a substrate, wherein the light reflection layer (20) comprises: a 1 st region (30) for displaying 1 st information by one or a combination of an outer edge shape and a shape of the concave-convex region; and a 2 nd information display region (21a) which is provided so as to partially or entirely overlap with the light reflection layer (20) that displays the 1 st information in the 1 st region (30) and displays identification information formed by removing a material locally from the light reflection layer (20).

Description

Information display medium and manufacturing method related thereto

Technical Field

The present disclosure is a technique relating to an information display medium. The present disclosure particularly relates to a technique suitable for an information display medium manufactured by irradiation of a pulsed laser beam.

Background

In order to protect an article such as a valuable paper such as a bank note or a gift certificate, a brand product, a high-priced product, an electronic device, or a personal authentication medium from value and information of the article, it is preferable that forgery is difficult. Therefore, anti-counterfeit techniques and information display methods that are difficult to counterfeit have been introduced for such articles.

For example, in order to make forgery difficult, an information display medium that is difficult to forge may be attached to the article, or a display portion may be formed in a part of the article.

For example, for forgery prevention of banknotes, certificates, tickets, and the like, a technique of forming a watermark pattern is generally known. A watermark pattern is obtained from a difference in thickness of a sheet when used as a document sheet, and therefore a technique of forming by embossing and a technique of forming by laser processing are also known (see patent document 1).

However, the current formation of a watermark pattern is performed when used as a document sheet, and therefore a watermark pattern that meets the requirements cannot be formed. Further, in order to form a watermark pattern by laser processing as in patent document 1, it is necessary to mix a pigment capable of absorbing a specific wavelength when used as a document paper, which raises a problem of cost increase.

Further, although the current watermark pattern is used for a paper substrate, in recent years, banknotes and the like using a polymer material composed of organic molecules as a substrate have started to be distributed, and therefore, a method for forming a watermark pattern on a substrate composed of organic molecules has not been established.

In addition, a method using forgery prevention ink is known as a display of a display portion which is difficult to forge. For example, patent document 2 describes that information is easily recognized in reflection observation by changing the spectral characteristics of reflected light using a specific coloring material or pigment.

In addition, as an information display method, an uneven structure such as a diffraction grating, a hologram, a lens array, or a scattering structure may be used. In order to form the above-described uneven structure, expensive manufacturing equipment such as an electron beam drawing device and a laser drawing device is required, and it is difficult to analyze the structure, so that the forgery prevention effect can be exhibited.

Further, patent document 3 discloses a method for manufacturing an optical element as follows, in which a structure forming layer including a region having a convex-concave structure with a large aspect ratio and a region having a flat or small aspect ratio is formed. That is, the metal reflective layer is formed on the structure formation layer by a vacuum evaporation method at a uniform surface density. Then, a material having durability against an etching solution for etching the metal reflective layer is formed to have a uniform surface density by a vacuum evaporation method. Next, the obtained laminate was used for etching treatment. In this way, since the material having durability to the etching liquid is formed into the discontinuous film due to the uneven structure having a large aspect ratio and the etching liquid is permeated, the metal reflective layer can be removed only in the region having the uneven structure having a large aspect ratio. Thus, the metal reflective layer can be formed with high positional accuracy, and the forgery prevention effect can be further improved.

However, with the method of patent document 3, although the metal reflective layer and the material having durability to the etching liquid are formed by the dry process, the wet process is utilized at the time of the etching treatment. Therefore, a plurality of processes are required for production, and the cost is increased.

In addition, when a material having durability against an etching solution is formed in advance, it is difficult to remove the metal reflective layer as required by removing the metal reflective layer so as to form only a fixed pattern.

Patent document 1: japanese patent No. 3486275

Patent document 2: japanese patent No. 2999354

Patent document 3: japanese patent No. 5051311

Disclosure of Invention

An object of the present disclosure is to provide an information display medium capable of improving an anti-counterfeit effect.

In order to solve the problems, one aspect of the present disclosure is a light-reflecting layer comprising 1 or more materials selected from metals, alloys, metal compounds, and semimetal compounds, the light-reflecting layer comprising: a 1 st region for displaying 1 st information by one or a combination of an outer edge shape and a shape of the concave-convex region; and a 2 nd information display region configured to partially or entirely overlap with a portion of the light reflection layer in the 1 st region, the portion displaying the 1 st information, and to display identification information by removing a material of a part of the light reflection layer.

Another aspect of the present disclosure includes an organic base material, and a drawing portion formed on the organic base material, the drawing portion including: a 1 st drawing section formed by a combination of a removal section formed by locally removing the surface of the organic substrate and a carbonized recess section formed by carbonizing the surface of the organic substrate and having a light transmittance lower than that at the removal section; and a 2 nd drawing portion which is finer than the 1 st drawing portion and is formed by a combination of a void portion formed inside the organic base material and a carbonized portion formed inside the organic base material and having a light transmittance lower than that of the void portion.

Another aspect of the present disclosure includes an organic substrate, and a drawing portion formed on the organic substrate, the drawing portion being formed by a combination of a removal portion formed by locally removing a surface of the organic substrate and a carbonized concave portion formed by carbonizing the surface of the organic substrate and having a light transmittance lower than a light transmittance at a position of the removal portion.

Another aspect of the present disclosure includes an organic substrate, and a drawing portion formed on the organic substrate, the drawing portion being formed by a combination of a void portion formed inside the organic substrate and a carbonized portion formed inside the organic substrate and having a light transmittance lower than that of the void portion.

ADVANTAGEOUS EFFECTS OF INVENTION

According to one embodiment of the present disclosure, an information display medium capable of improving an anti-counterfeit effect can be provided.

Further, for example, since additional materials for forgery prevention are not required and processing according to the demand can be realized, authentication information and identification information can be added.

Drawings

Fig. 1 is a partial cross-sectional view showing a part of a cross-sectional structure of an information display medium according to embodiment 1.

Fig. 2 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 1.

Fig. 3 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 1.

Fig. 4 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 1.

Fig. 5 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 1.

Fig. 6 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 1.

Fig. 7 is a front view showing an example of an information display medium according to embodiment 1.

Fig. 8 is a front view showing an example of an information display medium according to embodiment 1.

Fig. 9 is a plan view showing an example of the method for manufacturing the information display medium according to embodiment 1.

Fig. 10 is a partial cross-sectional view illustrating an example of the method for manufacturing the information display medium according to embodiment 1.

Fig. 11 is a schematic diagram showing an example of a method for manufacturing an information display medium according to embodiment 1.

Fig. 12 is a partial cross-sectional view showing a part of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 13 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 14 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 15 is a front view showing an example of an information display medium according to embodiment 2.

Fig. 16 is a partially enlarged plan view showing an example of the information display medium according to embodiment 2.

Fig. 17 is a partially enlarged plan view showing another example of the information display medium according to embodiment 2.

Fig. 18 is a partially enlarged plan view showing another example of the information display medium according to embodiment 2.

Fig. 19 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 20 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 21 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 2.

Fig. 22 is a plan view showing an example of a process for manufacturing the information display medium according to embodiment 2.

Fig. 23 is a plan view showing an example of a sub-area of the information display medium according to embodiment 2.

Fig. 24 is a plan view showing an example of a sub-area of the information display medium according to embodiment 2.

Fig. 25 is a plan view showing an example of a sub-area of the information display medium according to embodiment 2.

Fig. 26 is a front view showing an example of an information display medium according to embodiment 2.

Fig. 27 is a conceptual diagram for explaining a method of verifying an information display medium according to embodiment 2.

Fig. 28 is a partial cross-sectional view showing a part of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 29 is a partial sectional view showing a part of another example of the sectional structure of the information display medium according to embodiment 3.

Fig. 30 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 31 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 32 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 33 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 34 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 35 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 36 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 3.

Fig. 37 is a front view showing an example of an information display medium according to embodiment 3.

Fig. 38 is a conceptual diagram illustrating an example of the method for manufacturing the information display medium according to embodiment 3.

Fig. 39 is a cross-sectional view showing an example of the local application of energy according to embodiment 3.

Fig. 40 is a perspective view showing an example of the method of determining authenticity of an information display medium according to embodiment 3.

Fig. 41 is a front view showing another example of the information display medium according to embodiment 3.

Fig. 42 is a perspective view showing another example of the authentication method for an information display medium according to embodiment 3.

Fig. 43 is a partial cross-sectional view showing a part of the cross-sectional structure of the information display medium according to embodiment 4.

Fig. 44 is a partial perspective view showing a part of a structure forming layer of the information display medium according to embodiment 4.

Fig. 45 is a partial sectional view showing a part of another example of the sectional structure of the information display medium according to embodiment 4.

Fig. 46 is a partial cross-sectional view showing a part of another example of the cross-sectional structure of the information display medium according to embodiment 4.

Fig. 47 is a plan view showing an example of an information display medium according to embodiment 4.

Fig. 48 is a conceptual diagram illustrating an example of the method for manufacturing the information display medium according to embodiment 4.

Fig. 49 is a partial sectional view of an information display medium according to embodiment 1 of fig. 5.

Fig. 50 is a partial sectional view of an information display medium according to embodiment 2 of fig. 5.

Fig. 51 is a partial sectional view of an information display medium according to embodiment 3 of fig. 5.

Fig. 52 is a partial sectional view of the information display medium according to embodiment 4 of fig. 5.

Fig. 53 is a partial sectional view of an information display medium according to embodiment 5 of embodiment 5.

Fig. 54 is a partial sectional view of the information display medium according to embodiment 6 of fig. 5.

Fig. 55 shows an information display medium according to embodiment 7 of fig. 5, fig. 55(a) is a plan view showing a part of the information display medium, and fig. 55(B) is a partial sectional view of the information display medium.

Fig. 56 is a plan view showing a part of the information display medium according to embodiment 5 and 8.

Fig. 57 is a plan view showing a part of an information display medium according to embodiment 9 of fig. 5.

Fig. 58 is a diagram showing an example of a method for manufacturing an information display medium according to the present disclosure.

Fig. 59 is a partial cross-sectional view illustrating an example of a method for manufacturing an information display medium according to the present disclosure.

Fig. 60 is a front view of an information display medium according to the present disclosure.

Fig. 61 is a front view of an information display medium according to the present disclosure.

Detailed Description

Embodiments of the present disclosure will be described below with reference to the drawings.

Here, the drawings are schematic drawings, and the relationship between the thickness and the planar size, the ratio of the thicknesses of the respective layers, the shape of the recess, and the like are different from those in reality. The embodiments described below are examples of structures for embodying the technical idea of the present disclosure, and the materials, shapes, structures, and the like of the components relating to the technical idea of the present disclosure are not particularly limited to the embodiments described below. The technical idea of the present disclosure may be variously modified within the technical scope defined by the claims.

"embodiment 1"

Embodiment 1 based on the present disclosure will be explained.

The information display medium of the present embodiment includes, on one surface of a base material: a 1 st region in which a light reflection layer made of a metal or a metal oxide is locally disposed, and which displays 1 st information as authentication information by an outer edge shape of the light reflection layer; and a 2 nd information display area which is set in the light reflection layer for displaying the 1 st information in the 1 st area and displays the identification information formed by the partial removal of the light reflection layer. The shape of the outer edge of the light reflecting layer and the shape of the concave-convex area described in embodiment 2 may be combined, or the shape of the concave-convex area described in embodiment 2 may be used to form the 1 st information as the authentication information. The 3 rd information may be formed on the substrate itself, and the 3 rd information region and the 2 nd information display region may be separately overlapped.

The 1 st information is recorded as a pattern, for example. It is particularly preferable that the 1 st information formed of the pattern is a curved pattern. The 1 st information may be composed of color stripes, line drawings, geometric patterns, handwriting, logos, signs, portrait drawings, landmarks, landscapes, icons, symbols, or combinations thereof. Typically, the first information has an aesthetic appearance. Thereby enabling brand value to be increased.

The identification information formed on the light reflecting layer for displaying the 1 st information is, for example, a unique code, personal data (profile), serial number, specific mark, or the like, and is typically recorded as a minute character which is difficult to be observed with the naked eye. The information is difficult to observe by naked eyes, so that the appearance is not damaged, and on the other hand, the information can be easily recognized if the information is observed in a magnifying manner.

For example, the light reflection layer forming the 1 st information in the 1 st region is partially removed by a pulsed laser beam to form identification information.

In this way, by recording the identification information by locally removing the light reflection layer forming the 1 st information in the 1 st region, the first information and the identification information as the authentication information can be recorded indiscernibly, and thus tampering with the information display medium can be prevented. In addition, since the identification information is recorded so as to overlap with the authentication information, the display surface of the information display medium can be effectively used.

The valuable paper including the authentication information and the identification information can be configured by embedding or attaching the information display medium.

For example, such a valuable document may be verified by recognizing the authentication information of the information display medium by reflected light or transmitted light, and recognizing the 1 st information by magnifying and observing the authentication information of the information display medium by transmitted light.

Next, a configuration example (an example of partially removing) of the light reflection layer forming the 1 st region or the 2 nd information display region will be described. Fig. 1 to 6 are partial cross-sectional views showing an example of an information display medium 100 according to embodiment 1.

As is apparent from fig. 1 to 6, embodiment 1 is an example of a case where the surface (upper surface in the drawings) of the substrate 10 on which the light reflection layer 20 is formed is flat.

The information display medium 100 is constituted by a substrate 10 and a light reflection layer 20.

< substrate >

A resin-based masterbatch structure may be used for the substrate 10. Typically, the substrate 10 is plastic. As the resin, for example, 1 or 2 or more resins selected from thermoplastic resins, thermosetting resins, and photocurable resins can be used. The substrate 10 preferably has light-transmitting properties. The substrate 10 may have a single-layer structure or a multi-layer structure. The optical film may be made of a material having optical anisotropy, such as a liquid crystal material. Further, the resin may be colored by adding a dye, a pigment, or the like thereto.

As the material of the substrate 10, a metal oxide or a mixture thereof can be used. As the metal oxide or the mixture thereof, SiO may be used₂(silica), TiO₂(titanium dioxide) and MgO (magnesium oxide). The material of the base material 10 may be resin.

However, the substrate 10 has a refractive index different from that of the light reflecting layer 20.

In the case where the metal oxide is used as the substrate 10, the substrate 10 may be formed by, for example, a dry coating technique, or the substrate 10 may be formed by a wet coating technique such as gravure printing. Examples of the dry coating technique include evaporation, sputtering, and CVD (chemical vapor deposition).

When the resin is used as the substrate 10, the substrate 10 can be formed by, for example, extrusion molding, casting, or wet coating techniques. In addition, the base material 10 made of resin may be formed by a dry coating technique.

In addition, when the substrate 10 has light transmittance, information can be presented by the substrate 10 itself. For example, a relief hologram structure, a light scattering structure, a light interference structure, and the like are provided, and information can be recognized by visual observation due to optical effects of these structures.

The substrate 10 may be formed of a material that scatters and transmits light. Such a material is, for example, paper or the like. In this case, a watermark formed by changing the thickness of the paper may be provided to present information.

The thickness of the substrate 10 is preferably 5 μm or more and 200 μm or less. More preferably 20 μm or more and 150 μm or less. By providing such a thickness, the strength of the substrate 10 becomes sufficient for easy formation of the light reflection layer 20. In practice, the thickness of the light reflecting layer 20 may be a thickness necessary for reflection observation or see-through observation.

The substrate 10 may have a uniform film thickness in the same region, and the film thickness may be continuously or discontinuously changed.

< light reflection layer 20 >

The light reflecting layer 20 is formed on one surface of the substrate 10. The light reflection layer 20 may have a single-layer structure or a multi-layer structure.

As the material of the

light reflection layer

20, 1 or more kinds of materials selected from metals, alloys, metal compounds, and semimetal compounds can be usedAnd (5) feeding. As the metal, aluminum, silver, gold, copper, tin, nickel can be used. As the alloy, steel, stainless steel, or duralumin can be used. As the metal compound, zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO), or the like can be used₂) Zirconium dioxide (ZrO)₂) Titanium nitride, aluminum oxide, magnesium fluoride, tungsten oxide (WO)₃) Indium oxide (Y)₂O₃). As the semimetal compound, silicon dioxide or germanium oxide can be used. Particularly, a material having a metallic luster is preferable.

The light reflection layer 20 may be formed by vapor phase growth, for example. As the vapor phase growth, evaporation, sputtering, CVD (chemical vapor deposition) can be used. In addition, if the light reflecting layer 20 is provided, a wet coating technique such as a sol-gel method may be used.

The layer thickness of the light reflecting layer 20 is preferably 5nm or more and 100nm or less. More preferably 20nm or more and 60nm or less. By making the thickness of the layer thick, a sufficient reflectance of light can be obtained in visual observation, and the optical effect described below can be more easily seen.

The light reflecting layer 20 preferably has a uniform thickness in the same region, but the thickness may be continuously or discontinuously changed. Also, the light reflection layer 20 may form a periodic structure.

The light reflecting layer 20 forming the 1 st information or the identification information may be formed in a specific shape. As specific shapes, color stripes, line drawings, portrait drawings, landmarks, landscapes, symbols, marks, icons, handwriting, geometric figures, codes, numbers, signs can be exemplified. For example, in the case of forming the 1 st information, the decorativeness can be improved by a specific pattern composed of a linear or curved pattern. When the identification information is formed, for example, a specific pattern of a micro-engraved character may be formed.

In fig. 1, the light reflection layer 20 is formed with a region 112a by removing a part of the material by a manufacturing process described below.

When the information display medium 100 is observed in reflection in the region 112a, the reflectance is different between the region having the light reflection layer 20 and the region 112a from which the light reflection layer 20 is removed. When the light-reflecting layer 20 is made of a material having no light-transmitting property or has a thickness such that the light-transmitting property is lost when the information display medium 100 is viewed in a see-through manner, the transmittance is improved in the region 112 a.

Therefore, the 1 st information can be presented by using the region 112a in the reflection observation or the perspective observation.

Fig. 2 is an example of a cross-sectional view for explaining another configuration of the information display medium 100.

The information display medium 100 of fig. 2 shows an example in which an adhesive layer 13 for adhering the light reflection layer 20 to the substrate 10 and a protective layer 14 for preventing damage to the light reflection layer 20 are provided. In this case, for example, the region 112a can be provided by applying energy to a part of the light reflecting layer 20 with a pulsed laser.

In fig. 1, the region 112a is formed in a rectangular shape with a right angle at a corner of the cross section, but may be rounded or may be other than a rectangular shape. Next, a case different from the rectangular shape will be described with reference to fig. 3 to 6.

Further, the surface of the substrate 10 on the light reflecting layer 20 side in the lower portion of the region 112a where the light reflecting layer 20 is removed can be carbonized. By carbonizing the surface of the substrate 10 on the light reflection layer 20 side below the region 112a where the light reflection layer 20 is removed, light is absorbed in the region 112a where the light reflection layer 20 is removed, and the visibility of the region 112a is improved.

The information display media 100 of fig. 3 to 6 show an example in which the respective light reflection layers 20 are formed by being removed so as to have different cross-sectional structures.

The region 112b in fig. 3 shows a case where a part of the material of the light reflection layer 20 is penetrated to the base material 10 without being completely removed. Also, in the region 112b, the material of the light reflection layer 20 is removed in such a manner as to form a different thickness.

This causes the light reflection layer 20 to have a different thickness in the region 112b, and hence the transmittance differs for each thickness. Therefore, when the information display medium 100 is viewed in a see-through manner, a difference in transmittance of the region 112b can be visually observed.

Further, the light reflection layer 20 is thinned, thereby reducing the reflectance. Therefore, for example, when information is written on the substrate 10 and the information overlaps the region 112b, the reflectance of the region 112b is reduced, and thus the information formed on the substrate 10 can be confirmed in the case of reflection observation.

Fig. 4 shows a case where a region 112a obtained by removing the light reflecting layer 20 to penetrate the substrate 10 and a region 112c obtained by removing the light reflecting layer 20 with different thicknesses are formed at the same time.

Thereby, information obtained by completely removing the resulting region 112a of the light reflection layer 20 and information obtained by the region 112c of the light reflection layer 20 having different thicknesses can be combined.

In fig. 3, the light reflecting layer 20 in the region 112b has a rounded cross-sectional shape. In fig. 4, the cross-sectional shapes of the regions 112a and 112c are right-angled (stepped). In the present embodiment, the light reflection layer 20 may be formed in any cross-sectional shape as long as the transmittance and reflectance can be modulated.

Fig. 5 and 6 show a case where

structural cross sections

112d and 112e obtained by removing the material of the light reflecting layer 20 in the cross-sectional shape of the light reflecting layer 20 have a curved structure. This also provides the above-described effect in the case of the reflection observation and the effect in the case of the perspective observation.

The regions 112a to 112e obtained by partially removing the light reflection layer 20 can modulate the reflectance and transmittance of the light reflection layer 20 according to the size of the formation.

Here, when the lateral width of the region in which the regions 112a to 112e are formed is equal to or greater than 300 μm and equal to or less than 5mm, and more preferably equal to or greater than 500 μm and equal to or less than 3mm, the change in reflectance and transmittance of the light reflecting layer 20, which varies in thickness depending on the regions 112a to 112e, can be visually observed. In this case, a specific shape may be formed according to the 1 st region of the formation regions 112a to 112 e. The specific shape is, for example, a code, a symbol, a numeral, a character, or the like.

When the lateral widths of the regions in which the regions 112a to 112e are formed are greater than or equal to 500nm and less than or equal to 300 μm, and more preferably greater than or equal to 1 μm and less than or equal to 100 μm, the density of the regions 112a to 112e is varied, whereby variations in reflectance and transmittance of the light reflection layer 20 can be locally formed. Thus, the change in reflectance and transmittance can be visually observed.

On the other hand, specific shapes such as patterns, symbols, numerals, characters, geometric patterns, and the like can be formed in the regions where the regions 112a to 112e are formed, the lateral widths of the regions being greater than or equal to 500nm and less than or equal to 300 μm, and more preferably the regions 112a to 112e being greater than or equal to 1 μm and less than or equal to 100 μm. Thus, when the areas 112a to 112e are enlarged and the perspective observation or the reflection observation is performed, the 2 nd information display area in which a specific shape can be observed can be set.

As described above, by adjusting the lateral width of the region where the light reflection layer 20 is partially removed, the material is partially removed from the 1 st region where the 1 st information is formed and the light reflection layer 20 where the 1 st information in the 1 st region is formed, and the 2 nd information display region where the identification information is formed can be set.

Fig. 7 shows the information display medium 200 including the

regions

120, 121, 122, 123, 124, and 21 of the light reflection layer 20 having different reflectances and transmittances due to partial removal. Fig. 7(a) shows an external appearance of the information display medium 200, and fig. 7(b) shows an enlarged view of a part 125 of the information display medium 200.

Here, in fig. 7, the

regions

120, 121, 122, 123, and 124 are the 1 st regions, and as shown in fig. 7(b), the region 21 overlapping with the region 120 is the 2 nd information display region. Further, a part of the region 21 may be set to be exposed from the region 120. A portion of the removed portion of material forming the identification information may be disposed within the area 120.

The region 120 is a 1 st region formed to penetrate the substrate 10 and remove the light reflection layer 20 to realize a pattern, that is, to display the 1 st information in the shape of the outer edge. The

regions

121, 122, 123, 124, and 21 are regions in which the amount of removal of the light reflecting layer 20 is different.

If the information display medium 200 is visually observed by reflection, the reflectance of the information display medium 200 differs from region to region due to the difference in the amount of removal of the light reflection layer 20, and therefore the difference can be visually confirmed. Particularly in the case where metal is used as the light reflection layer 20.

In addition, when information is formed on the substrate 10, the transmittance is different in the regions 120 to 124, and therefore the information formed on the substrate 10 can be observed in visual reflection observation. This enables more complicated information to be presented.

When the information display medium 200 is visually observed in a see-through manner, the transmittance of the information display medium 200 differs in each region due to the difference in the amount of removal of the light reflection layer 20, and the difference can be visually confirmed.

In the information display medium 200, the region 120 is formed into a line shape, the region 121 is formed into a crescent shape, and the regions 122 to 124 are formed into a pattern shape of a star shape. Actually, the pattern may be formed not only by a pattern but also by a specific shape such as a symbol, a numeral, a character, a geometric pattern, or the like.

Further, by further removing a part of the light reflection layer 20 in each region, regions having different information in the regions can be formed.

For example, in fig. 7(b), in the region 125, the light reflection layer 20 is partially removed by a part of the region 120 included in the region 125, thereby providing a region 21 for displaying identification information. As the identification information, it is preferable to use a minute character such as a specific symbol such as a character, a numeral, a code unique to a combination of symbols, personal data, a serial number, and "AB +". Thus, when the information display medium 200 is enlarged and viewed in perspective or in reflection, the identification information in the area 21 constituting the 2 nd information display area can be further identified in the area 120.

Further, by forming the identification information by irradiation of the pulse laser light, a minute character or the like can be formed in a minute area easily.

As described above, by locally removing the light reflection layer 20 for each region and modulating the removal amount, a plurality of pieces of information can be added to one information display medium 200 so that the regions overlap. In addition, the plurality of pieces of information can be confirmed in the case of reflection observation or perspective observation.

Fig. 8 shows an information display medium 200 including

regions

120, 121, 122, 123, 124, 126 of different reflectivities and transmittances of the light reflection layer 20. Fig. 8(a) shows an external appearance of the information display medium 200, and fig. 8(b) and 8(c) show enlarged views of a part 127 of the information display medium 200.

The region 120 is a region where the light reflecting layer 20 is removed so as to penetrate through the substrate 10. The

regions

121, 122, 123, 124, and 126 are regions in which the amount of removal of the light reflecting layer 20 is different.

If the information display medium 200 is visually observed by reflection, the reflectance of the information display medium 200 differs from region to region due to the difference in the amount of removal of the light reflection layer 20, and therefore the difference can be visually confirmed. Particularly in the case where a metal material is used as the light reflection layer 20.

In addition, when information is formed on the substrate 10, the transmittance is different in the regions 120 to 124, so that the information formed on the substrate 10 can be observed in visual reflection observation. This enables more complicated information to be presented.

The information display medium 200 has a pattern shape in which the region 120 is formed in a linear shape, the region 121 is formed in a crescent shape, and the regions 122 to 124 are formed in a star shape. In fact, the pattern may be formed not only in a pattern but also in other specific shapes. Other specific shapes are symbols, numbers, characters, geometric patterns, etc.

Further, by further removing the light reflection layer 20 in each region, regions having different information in the region can be formed.

Here, when different information is formed, even if the pattern recorded by the laser is formed as a pattern that appears repeatedly and a position thereof is displaced with respect to the reflective layer 20, the pattern recorded by the laser can be recognized. The laser light 50 is controlled to always scan in a specific direction, and the repetition interval of the formed pattern is made different from the arrangement interval of the color stripes and the like of the region 20, or the arrangement direction is made different, and adjusted so that the pattern converges to the width of the color stripes. This allows further information to be checked using an arbitrary portion of the area 120 as shown in fig. 8 (b).

For example, fig. 8(b) shows character information in which a portion of the region 120 included in the region 127 and in the region 127 is further partially removed by the light reflection layer 20 to provide a region 126. Actually, the information may be not only character information but also patterns, symbols, numbers, geometric patterns, and the like. Thus, when the information display medium 200 is enlarged and viewed in perspective, the region 126 can be further recognized within the region 120. The region 126 overlapping with the region 120 becomes the 2 nd information display region. Further, a part of the region 126 may be set to be exposed from the region 120. A portion of the removed portion of material forming the identification information may be disposed within the area 120.

In fig. 8(c), the laser light 50 is scanned in the laser scanning direction B to generate the region 126 in fig. 8 (B).

In fact, the laser scanning direction may be not only a straight line but also a curved line, and may be a scan capable of forming further information on the region 120 formed in advance on the information display medium 200.

< method for manufacturing information display Medium >

Next, a method for manufacturing the

information display media

100 and 200 will be described.

After the light reflection layer 20 is formed on the substrate 10, energy is locally applied to the light reflection layer 20 by laser light or the like to locally remove the light reflection layer 20 or completely remove the light reflection layer 20, thereby manufacturing the

information display media

100 and 200.

Alternatively, after the light reflection layer 20 is formed on the substrate 10, the light reflection layer 20 is partially removed or the light reflection layer 20 is completely removed by further forming a pattern cover layer 140 on the light reflection layer 20 and performing chemical treatment as shown in fig. 10, thereby manufacturing the

information display media

100 and 200.

As a method of locally applying energy to the light reflecting layer 20, there is a method of using a pulsed laser light source or a thermal head. Further, a diagram in the case of using a pulsed laser light source is shown in fig. 9.

The laser light emitted from the pulsed laser light source 52 passes through the lens 51 and is reflected by the mirror 53, and is condensed and incident on the light reflection layer 20 forming the

information display media

100 and 200. Then, the energy of the laser beam is locally focused on the focal point, and the light reflecting layer 20 is melted and volatilized by the energy to be removed. When the material is removed so as to penetrate through the light reflecting layer 20, the light does not necessarily have to be converged toward the light reflecting layer 20.

When processing is performed with a laser beam, the

information display medium

100 or 200 is moved, or the three-dimensional coordinates of the focal position X, Y, Z of the laser beam 50 are controlled, whereby the region from which the light reflection layer 20 is removed can be set.

Alternatively, the reflecting mirror 53 has a micromirror array structure, and the phase of the laser beam can be controlled and the focal position of the laser beam can be controlled by controlling the micromirror array structure with a computer.

Further, as the pulsed laser source 52, it is preferable that the pulse width is greater than or equal to 100 femtoseconds and less than or equal to 1 picosecond. This allows the laser beam to pass through the lens 51 and instantaneously enter a high-energy state at the focal position, thereby removing the light reflecting layer 20 or cutting the light reflecting layer 20. In addition, the time in the high energy state is very short, and thus the influence is concentrated on the irradiation position.

When the light reflecting layer 20 is removed by the laser beam 50, the following system may be assembled in order to accurately align the removal position.

As shown in fig. 11, the reflected light from the substrate 10 or the light reflecting layer 20 of the laser beam 50 is measured by a detector 54 through a half mirror 53. This enables monitoring of the change in the intensity of the reflected light via the detector 54. That is, whether or not the light reflecting layer 20 is provided on the substrate 10 can be confirmed.

However, when the intensity of the laser light 50 is strong, there is a possibility that the laser light 50 is removed at the moment when it is irradiated to the light reflection layer 20, and therefore, it is necessary to monitor the intensity change of the reflected light by the detector 54 in a state where the light intensity of the laser light 50 is reduced. Alternatively, it is necessary to monitor the change in the intensity of the reflected light by the detector 54 in a state where the focal position of the laser light 50 is shifted from the surface of the substrate 10.

As shown in fig. 11, when the substrate 10 is conveyed in the substrate conveying direction a, the reflected light intensity increases in the detector 54 when the laser light 50 is irradiated onto the light reflection layer 20, and thus it is understood that the light reflection layer 20 is in a region where the laser light 50 can be irradiated. Then, a predetermined processing pattern is formed on the light reflecting layer 20 by the laser beam 50, thereby processing can be performed in accordance with the position of the light reflecting layer 20.

Further, the mirror 53 may be a reflective spatial light modulator, and the phase of each cell of the spatial light modulator may be controlled by a computer, thereby controlling the phase of the laser light and controlling the focal position of the laser light. Further, the spatial light modulator may be a transmissive structure.

The spatial light modulator may control the focal position of the laser light, and may control the focal length of the laser light 50 and divide and condense the laser light 50 into a plurality of laser light beams.

By increasing the focal length of the laser beam 50, stable processing can be achieved without being affected by external disturbances such as vibration of the apparatus when removing the light reflecting layer 20.

As a method of increasing the focal length of the laser light 50, in addition to the method using the spatial light modulator as described above, the focal length may be increased by replacing the lens 51 with an axicon lens or the like.

As a method of performing chemical treatment on the light reflecting layer 20, as shown in the diagram of fig. 10, a patterned cover layer 140 is locally provided on the light reflecting layer 20, and the light reflecting layer 20 can be partially removed or the light reflecting layer 20 can be completely removed by performing chemical treatment (wet etching, dry etching, or the like).

After the light reflection layer 20 is partially removed or the light reflection layer 20 is completely removed, the pattern cover layer 140 may be left as it is or the pattern cover layer 140 may be removed.

Fig. 10 shows an example in which the pattern cover layer 140 is provided in a dot pattern, but the pattern cover layer may be not only a dot pattern but also a line pattern, a flat pattern, or the like. Alternatively, the patterned overlay 140 may be used to form specific patterns such as patterns, symbols, numbers, characters, geometric patterns, and the like.

The above-described manufacturing method can be applied after the

information display medium

100, 200 is formed, and thus can be applied as a post-processing method for a manufacturing line of the

information display medium

100, 200. In addition, in the case of using a manufacturing method in which energy is locally applied, processing suitable for the

information display media

100 and 200 can be realized.

In the case of a manufacturing method using chemical treatment, the metal foil may be etched simultaneously with post-processing.

As described above, if the manufacturing method of the present disclosure is applied to the

information display media

100 and 200, different optical expressions are realized in the

respective regions

120, 121, 122, 123, 124, 21, and 126 of the information display medium 200 shown in fig. 7 and 8, and different pieces of information can be provided. The

information display media

100 and 200 can be determined to be genuine by the combination of the optical expressions and the combination of the information.

"embodiment 2"

Next, embodiment 2 according to the present disclosure will be described with reference to the drawings.

Embodiment 2 is an example of a case where the substrate has a structure forming layer having an uneven structure, and the 1 st information is displayed in the metal reflective layer in the shape of an uneven region by the unevenness.

In the drawings, the same reference numerals are used for components that perform the same or similar functions, and redundant description is omitted.

Fig. 12 to 14 are partial cross-sectional views showing an example of an information display medium according to the present embodiment. A partial cross-sectional view in the case where the light reflection layer 20 has the 2 nd information display region 21 from which a part of the material forming the light reflection layer 20 is removed is shown.

In embodiment 2, a structure forming layer is formed on a surface layer of a substrate. Fig. 12 shows an example in which the substrate is constituted by the structure forming layer 10.

(embodiment mode 1)

In the information display medium 100 according to embodiment 1 shown in fig. 12, the structure forming layer 10 has: a 1 st region 30 having a concave-convex structure; and a 2 nd region 31 formed with a flat configuration. Further, a light reflecting layer 20 is formed on the interface where the above structure is formed. The 1 st region 30 includes the 2 nd information display region 21 in which a part of the light reflection layer 20 is removed. Thereby, the 1 st information displayed in the shape of the concave-convex area is formed in the 1 st area 30, and the identification information is formed in the 2 nd information display area 21.

The 2 nd region 31 does not need to have a flat surface shape, and may have a surface shape having a roughness smaller than that of the 1 st region 30. The same applies to the other embodiments below.

The roughness can be measured, for example, by using an arithmetic average roughness (Ra: JIS B0601).

For the substrate having the structure forming layer 10, the resin may be used as a master batch. Typically, the substrate is plastic. As the resin, a thermoplastic resin, a thermosetting resin, or a photocurable resin can be used. Preferably, the substrate has light-transmitting properties. The substrate having the structure forming layer 10 may have a single-layer structure or a multi-layer structure. The optical film may be made of a material having optical anisotropy, such as a liquid crystal material. Further, the resin may be colored by adding a dye, a pigment, or the like to the resin.

As the material of the substrate, a metal oxide or a mixture thereof can be used. As the metal oxide or the mixture thereof, SiO may be used₂(silica), TiO₂(titanium dioxide) and MgO (magnesium oxide). Also, the material of the base material may be a resin. However, the base material has a refractive index different from that of the light reflection layer 20.

In the case where the metal oxide is used as the substrate, the substrate may be formed by, for example, a dry coating technique or a wet coating technique such as gravure printing. Examples of the dry coating technique include evaporation, sputtering, and CVD (chemical vapor deposition).

When the resin is used as a base material, it can be formed by, for example, extrusion molding, casting, or wet coating techniques. Alternatively, the coating layer may be formed by a dry coating technique.

In addition, when the base material has light transmittance, information can be presented by the base material itself. For example, by providing a relief hologram structure, a light scattering structure, a light interference structure, or the like, information can be recognized in visual observation by the optical effect of the above-described structure.

The thickness of the substrate is preferably 5 μm or more and 200 μm or less. More preferably 20 μm or more and 150 μm or less. By setting the thickness to the above-described thickness, the strength of the base material is formed to be sufficient for easy formation of the light reflection layer 20. In practice, the thickness of the light reflecting layer 20 may be a thickness necessary for reflection observation or see-through observation.

As shown in fig. 12, the light reflecting layer 20 is formed at the interface where the uneven structure (the portion of the 1 st region) and the flat structure (the portion of the 2 nd region) are formed in the structure forming layer 10. Further, the structure may be a single layer structure or a multilayer structure. The flatness means a roughness smaller than that of the surface of the uneven structure.

As a material of the light reflection layer 20, a metal, an alloy, a metal compound, and a semi-metal compound can be used. As the metal, aluminum, silver, gold, copper, tin, nickel can be used. As the alloy, steel, stainless steel, or duralumin can be used. As the metal compound, zinc sulfide (ZnS), zinc oxide (ZnO), titanium dioxide (TiO), or the like can be used₂) Zirconium dioxide (ZrO)₂) Titanium nitride, aluminum oxide, magnesium fluoride, tungsten oxide (WO)₃) Indium oxide (Y)₂O₃). As the semimetal compound, silicon dioxide or germanium oxide can be used. The material of the light reflection layer 20 is particularly preferably a material having a metallic luster.

In addition, the light reflection layer 20 may be formed by vapor phase growth. As the vapor phase growth, evaporation, sputtering, CVD (chemical vapor deposition) can be used. As long as the light reflecting layer 20 is provided, wet coating techniques such as a sol-gel method may be used.

The layer thickness of the light reflecting layer 20 is preferably 5nm or more and 100nm or less. More preferably 20nm or more and 60nm or less. This makes it possible to obtain a sufficient light reflectance during visual observation.

The light reflecting layer 20 may have a uniform film thickness in the same region, and the film thickness may be continuously or discontinuously changed. Also, the light reflection layer 20 may form a periodic structure.

The light reflecting layer 20 may be formed in a specific shape. The specific shape is a symbol, a number, a character, a geometric pattern, or the like.

The 2 nd information display area 21 may be formed in a specific shape in the entire 1 st area 30, but may be formed only in a part of the 1 st area 30. In addition, for example, the 2 nd information display region 21 is formed by removing a material forming the light reflection layer 20 in a range of 50% or more and 100% or less per unit area. The unit area in this case may be a unit surface area (for example, 1 square mm) of the surface of the substrate 10.

The method of forming the 2 nd information display area 21 will be described in detail later.

(embodiment mode 2)

The basic configuration of the information display medium 100 according to embodiment 2 shown in fig. 13 is the same as that of the information display medium 100 according to embodiment 1. However, embodiment 2 is an example of a case where the 2 nd information display region 21 is set by removing a material from the light reflection layer 20 located in a partial region within the 1 st region 30. Fig. 13 also shows an example of a method for forming the 2 nd information display area 21. The method of forming the 2 nd information display area 21 shown in fig. 13 can also be applied to embodiment 1 described above.

The information display media 100 according to

embodiments

1 and 2 are examples of a case where the 2 nd information display area is completely included in the 1 st area.

The method of forming the 2 nd information display area 21 illustrated in fig. 13 is as follows.

In embodiment 2, a method for forming the 2 nd information display region 21 for identification information is exemplified in the case where the material of the light reflection layer 20 is locally removed by irradiation with laser light.

In the formation, the identification information is formed by making the laser light 50 condensed by the lens 51 enter the structure-forming layer 10 from the interface facing the interface on which the structure is formed, with respect to the average layer thickness H of the structure-forming layer 10 in fig. 13, and moving the condensed position of the laser light 50 based on the preset drawing data.

At this time, the converging position of the laser beam 50 is set to be shifted from the interface where the uneven structure is not formed of the structure forming layer 10 to a position closer to the front side (the side away from the light reflecting layer 20) than the position of half of the average layer thickness H, whereby the 2 nd information display region 21 is formed by removing a part of the material forming the light reflecting layer 20 in the 1 st region 30 where the uneven structure is formed in the structure forming layer 10. At this time, in the 2 nd region 31 in which the flat structure is formed in the structure forming layer 10, the power is adjusted so that the material forming the light reflecting layer 20 is not removed or the amount of material forming the light reflecting layer 20 removed per unit area is less than 30%. The power may be adjusted as appropriate in such a manner that the amount of material forming the light reflection layer 20 removed per unit area is less than 15%.

(embodiment mode 3)

The basic configuration of the information display medium 100 according to embodiment 3 shown in fig. 14 is the same as that of the information display medium 100 according to embodiment 1. However, embodiment 3 is an example of a case where the 2 nd information display region 21 is set by removing a material from the light reflection layer 20 located in a partial region of both the 1 st region 30 and the 2 nd region 31. An example of a method of forming the 2 nd information display area 21 is also shown.

The information display medium 100 according to embodiment 3 is an example in which a part of the 2 nd information display area 21 is set to overlap the 1 st area 30.

In the formation, the identification information is formed by causing the laser light 50 condensed by the lens 51 to enter from the interface of the structure forming layer 10 facing the interface where the structure is formed, with respect to the average layer thickness H of the structure forming layer 10 in fig. 14, and moving the condensed position of the laser light 50 based on the preset drawing data.

At this time, the converging position of the laser beam 50 is set and moved to a position on the back side (light reflection layer 20 side) from the interface where the uneven structure is not formed of the structure forming layer 10 to the position half the average layer thickness H, and the 2 nd information display region 21 is formed by removing a part of the material forming the light reflection layer 20 in the 2 nd region 31 where the flat structure is formed, in addition to the 1 st region 30 where the uneven structure is formed in the structure forming layer 10. At this time, in the structure forming layer 10, even in the 2 nd region 31 where a flat structure is formed, power is modulated in such a manner that the amount of material forming the light reflection layer 20 removed per unit area is 50% or more. In this embodiment, the power of the laser beam and the like are set under the same conditions, and embodiment 2 and embodiment 3 are implemented.

The 2 nd information display area 21 formed by the 1 st area 30 and the 2 nd area 31 is not formed over the entire area of the 1 st area 30 and the 2 nd area 31, but is formed locally.

In fig. 13 and 14, an arrow a shows an example of the scanning direction of the laser beam 50.

Here, as described above, in fig. 13, the 2 nd information display region 21 is formed only in the 1 st region 30 in which the concave-convex structure is formed in the region scanned with the laser light 50. In fig. 14, the 2 nd information display region 21 is formed in both the 1 st region 30 where the uneven structure is formed and the 2 nd region 31 where the flat structure is formed in the region scanned with the laser light 50.

In this way, even if the same power is set, the region forming the 2 nd information display region 21 can be made to overlap only the 1 st region 30 or both the 1 st region 30 and the 2 nd region 31 by adjusting the focal position and scanning the laser beam 50.

Here, the method of forming the 2 nd information display area 21 may be not only a method of scanning and drawing with the laser light 50 described above, but also a method of controlling an area irradiated with the laser light 50 with a photomask, a method of controlling a direction irradiated with the laser light 50 with a liquid crystal screen, a method of controlling a direction irradiated with the laser light 50 with a mirror array, a method of controlling a direction irradiated with the laser light 50 with a galvanometer mirror, and the like.

Here, when the 2 nd information display region 21 is formed by irradiation of the laser light 50, the material forming the light reflection layer 20 receives energy from the laser light 50, and the material forming the light reflection layer 20 is sublimated by heat generated by the energy, thereby removing the material. The material forming the light reflecting layer 20 may be decomposed or carbonized without being sublimated. When the material is decomposed and carbonized, the decomposed and carbonized material cannot be seen by human eyes (average diameter is 300 μm or less), and therefore, the decomposed and carbonized material cannot be visually confirmed in normal observation, and thus the decomposed and carbonized material can be used for displaying information without any problem.

In addition, in the 2 nd information display region 21, the material forming the light reflection layer 20 is removed by 50% or more per unit area, so that the reflectance of the 2 nd information display region 21 is reduced in the 2 nd information display region 21 and other regions where the light reflection layer 20 is not removed at the time of reflection observation of the information display medium 100. Alternatively, in the perspective view of the information display medium 100, the transmittance of the 2 nd information display region 21 is improved in the 2 nd information display region 21 and the other regions where the light reflection layer 20 is not removed. The 2 nd information display region 21 is a portion of the light reflection layer 20 from which material has been removed by the laser beam, but the identification information is not limited to the portion from which material has been removed, and may be displayed in a portion between the removed materials.

This makes it possible to combine a plurality of pieces of information displayed on the information display medium 100 and to display the information by superimposing 2 or more pieces of information. For example, information presented by the concave-convex structure formed in the 1 st region 30 and information presented by the 2 nd information display region 21 formed by the laser light 50 may be included in the information display medium 100 in a state where the regions overlap.

Since the information presented in the 2 nd information display area 21 is information presented as minute characters or the like which are hidden in the information recorded in the 1 st area 30, it can be presented for the first time in the case of the reflection observation or the perspective observation, and the identification information can be embedded in the information display medium 100 like the latent image information. In the example of embodiment 3, the 2 nd information display region 21 is also formed in the 2 nd region, but when the identification information is the latent image information, the area of the 2 nd information display region 21 formed in the 2 nd region is set to 30% or less, preferably 15% or less.

Here, since the identification information formed in the 2 nd information display region 21 is formed by condensing the laser light 50, it can be formed with a narrow region width and the region width can be modulated. Specifically, the region width can be modulated to 1 μm to 100 μm by 1 laser scanning. Further, the width of the 2 nd information display region 21 can be modulated by reducing the scanning pitch when scanning with the laser light 50 or by changing the distance to the light reflection layer 20.

Further, as described above, in order to set the identification information presented by the 2 nd information display region 21 as a latent image, the region width of the 2 nd information display region 21 may be set to 1 μm to 300 μm. Depending on the resolution of the human eye, it is generally difficult to visually observe a line width of 300 μm or less at the time of observation. Further, since the identification information is embedded in the 1 st information region, it is more difficult to visually observe the identification information.

In contrast, by setting the region width of the 2 nd information display region 21 to the order of mm, the identification information can be visually observed at the time of normal observation.

As the laser 50, an intermittent laser (pulse laser) is preferable to a continuous excitation laser (CW laser), and more specifically, a picosecond laser and a femtosecond laser are preferable.

The picosecond laser in the pulsed laser may be a laser excited by an optical fiber or a solid crystal. Examples of the femtosecond laser include a laser excited by an optical fiber or a solid crystal (titanium sapphire crystal or the like).

Since the pulse widths of the laser pulses of the picosecond laser beam and the femtosecond laser beam are very short, the laser beams are condensed and irradiated, and thus very strong energy is generated in a minute space near the condensed point. The material forming the light reflection layer 20 is sublimated, or decomposed or carbonized into a fine material by the energy or heat accompanying the energy, and the material is removed.

The pulsed laser can instantaneously apply high energy to the laser focal point, and as a result, sublimation, decomposition, and carbonization of the material occur. Therefore, it is not necessary to use a laser absorbing material, a laser heat generating material, or the like, which are currently required for generating identification information, and manufacturing cost can be reduced. In addition, a material having a repetition frequency of pulses of 1kHz to 1GHz can be used. By changing the repetition frequency, the power of the laser can also be modulated. In addition, the power can be modulated by changing the Q value.

(embodiment mode 4)

The information display medium 100 according to embodiment 4 shown in fig. 15 includes, as the 2 nd information display area 21: a 2 nd information display region 21a formed to be included in the 1 st region 30 in which the concave-convex structure is formed; and a 2 nd information display area 21b formed to cross the 1 st area 30 and the 2 nd area 31.

The relief structure in the 1 st region 30 is a relief structure or a random dot structure. As the relief structure, a 1-dimensional relief structure or a 2-dimensional relief structure can be used.

The 1-dimensional relief structure is, for example, a structure in which grid vectors are parallel to the X direction and the Y direction, or a structure in which the grid vectors are aligned in a direction forming a specific angle with the X, Y direction. The 2-dimensional relief structure has grid vectors in 2 directions, which are aligned in a direction forming a specific angle with respect to the direction X, Y, for example, in parallel with the X direction and the Y direction, respectively.

The cross section of the relief structure is in a wave shape, a sawtooth wave shape, a square wave shape, a step shape and the like.

Specifically, in fig. 15, the 2 nd information display region 21a is formed only in the 1 st region 30, and identification information such as a numeral "12345" is formed in the 1 st region 30 by removing a material forming the light reflection layer 20. The 2 nd information display region 21b is formed across the 1 st region 30 and the 2 nd region 31, and a geometric pattern such as a color pattern is formed as identification information by removing a material forming the light reflection layer 20.

In fig. 15, the 1 st region 30 having the uneven structure is presented with information different from the identification information presented in the 2 nd information display region 21a by reflection, diffraction, refraction, interference, or scattering of light generated by the uneven structure. Here, the shape of the 1 st information and the 2 nd information display area 21b, which are formed by the concave-convex structure, may be a background pattern, a decoration, or the like, and may not clearly show a particular content.

Further, more preferably, the lines forming the 2 nd information display areas 21a and 21b are formed by relatively fine line drawings, geometric patterns, color stripes, and handwriting in some cases. Thus, when the 2 nd information display regions 21a and 21b are observed in an enlarged manner, different pieces of identification information can be presented.

Further, in the manufacturing process of the information display medium 100, the 2 nd information display regions 21a and 21b may be formed so as to present different information for each manufactured information display medium 100. This is because the light reflection layer 20 can be removed by the laser light 50 based on information different from one another.

(embodiment 5)

Another example of the method for forming the 2 nd information display region will be described.

The area 70 is the 2 nd information display area, and embodiment 5 is an example in which the area 70 is formed only in the 1 st area 60.

An information display medium 100 according to embodiment 5 shown in fig. 16 is a diagram illustrating an example of a case where a laser beam 50 is moved across a 1 st region 60 and a 2 nd region 61 to form a region 70. The 1 st region 60 includes 3

sub-regions

62a, 62b, and 62 c. The broken-line arrow denoted as PATH indicates the PATH through which the laser beam 50 passes.

In fig. 16, the laser light 50 is incident from the interface facing the side of the uneven structure where the 1 st region 60 is formed and the side of the flat structure where the 2 nd region 61 is formed, and the focal position of the laser light 50 is set to be farther from the light reflecting layer 20 side than half of the average layer thickness H of the structure forming layer 10. Therefore, as described above, the light reflection layer 20 of the 1 st region 60 having the uneven structure is removed, and the light reflection layer 20 of the 2 nd region 61 is not removed, so that the wavy line pattern of the region 70 is formed only in the 1 st region 60.

(embodiment mode 6)

The area 70 is the 2 nd information display area, and embodiment 6 is an example in which the area 70 is formed across the 1 st area 60 and the 2 nd area 61.

An information display medium 100 according to embodiment 6 shown in fig. 17 is a diagram illustrating another example of the formation of the region 70 in the case where the laser beam 50 moves across the 1 st region 60 and the 2 nd region 61. The 1 st region 60 includes 3

sub-regions

In fig. 17, the laser light 50 is incident from the interface facing the side where the uneven structure forming the 1 st region 60 is formed and the side where the flat structure forming the 2 nd region 61 is formed, and the focal position of the laser light 50 is set to be deeper than half the average layer thickness H of the structure-forming layer 10 (the side close to the light-reflecting layer 20). Therefore, as described above, the light reflection layer 20 in which both the 1 st region 60 and the 2 nd region 61 having the uneven structure are formed is removed, and in embodiment 6, the wave line pattern of the region 70 is formed so as to extend over the 1 st region 60 and the 2 nd region 61.

Here, in the example shown in fig. 16 and 17, 3

sub-regions

62a, 62b, and 62c are periodically arranged in the 1 st region 60, but information may be presented by reflection, diffraction, refraction, interference, and scattering of light of the concave-convex structure formed in the

sub-regions

62a, 62b, and 62c by arranging the

sub-regions

62a, 62b, and 62c as characters, numerals, patterns, geometric patterns, and color-grain patterns.

In addition, by irradiating the laser light 50 along the characters, numerals, patterns, geometric patterns, color-grain patterns, and the like formed by the sub-areas 62a, 62b, 62c, it is possible to align the information formed by the sub-areas 62a, 62b, 62c and the position information of the information obtained by the area 70 formed by using the laser light 50 without error.

In fig. 16 and 17, a vector scanning method in which the laser beam 50 is moved along the region 70 as in the PATH is used to form the region 70, but the region may be formed by a raster scanning method.

Further, the region 70 may be formed by a vector scan or a raster scan method by forming an image of the laser beam 50 at a single focal point, or the region 70 may be formed in a uniform manner in a specific area region by forming an image of the laser beam 50 at a plurality of focal points. In addition, in the case where the laser light 50 is imaged at a plurality of focal points, the region 70 may be formed by forming characters, numerals, patterns, geometric patterns, color stripe patterns, or the like using the plurality of focal points.

(embodiment 7)

An information display medium 100 according to embodiment 7 shown in fig. 18 is a diagram illustrating another example in which a laser beam 50 moves across the 1 st region 60 and the 2 nd region 61 to form a region 70. In embodiment 7, the 1 st region 60 includes 4

sub-regions

62a, 62b, 62c, and 62 d. The broken-line arrow denoted by PATH indicates a PATH through which the laser beam 50 passes.

In fig. 18, the laser light 50 is incident from the interface facing the side of the uneven structure where the 1 st region 60 is formed and the side of the flat structure where the 2 nd region 61 is formed, and the focal position of the laser light 50 is set to be closer to the front side (the side away from the light reflecting layer 20) than half of the average layer thickness H of the structure forming layer 10. Therefore, as described above, only the light reflection layer 20 of the 1 st region 60 having the uneven structure is removed, and the region 70 is formed in the 1 st region 60.

Here, in embodiment 7, the aspect ratio of the uneven structure in which the

sub-regions

62a, 62b, and 62c are formed is set to 0.1 or more and 1 or less, and the aspect ratio of the uneven structure in which the sub-region 62d is formed is set to 1 or more and 2 or less.

The aspect ratio of the uneven structure is different, so that the surface area of the uneven structure surface is different. When the aspect ratio of the uneven structure is high, the surface area is large, and therefore, when the light reflection layer 20 is formed, the apparent layer thickness of the light reflection layer 20 is formed to be thin in a region with a low aspect ratio and a region with a high aspect ratio.

Therefore, when the laser beam 50 is irradiated, the layer thickness of the light reflecting layer 20 is thin in a region with a high aspect ratio, and thus the removal is easy.

In fig. 18, since the aspect ratio of the uneven structure is high in the sub-region 62d, when the laser light 50 is irradiated along the PATH in the raster scan manner, the light reflection layer 20 of the sub-region 62d is removed more than the

sub-regions

62a, 62b, and 62c, and becomes the region 70. In fig. 16, since the sub-area 62d is arranged as a character such as "OK", if the information display medium 100 is irradiated with the laser light 50 while being scanned, the character such as "OK" is formed as identification information and displayed in the area 70.

The information of the sub-area 62d or the area 70 shown in fig. 18 may be presented not only for character information but also for information such as numerals, patterns, geometric patterns, and color-pattern patterns.

(embodiment mode 8)

The information display medium 200 according to embodiment 8 shown in fig. 19 has the same structure as the information display medium 200 according to embodiments 1 to 3, and the adhesive layer 40 is formed on the light reflecting layer 20.

Having the adhesive layer 40 enables the information display medium 200 to be attached to various substrates 41. For example, as in the information display medium 200 shown in fig. 20, the adhesive layer 40 may be configured to be adhered to the base material 41.

As shown in fig. 19 and 20, the information display medium 200 has a structure in which not only the structure forming layer 10 has a concave-convex structure or a flat structure, but also the structure forming layer 10 itself functions as a protective layer for protecting the concave-convex structure or the flat structure. In practice, the structure forming layer 10 may be formed with a protective layer on the side where the uneven structure is not formed and the flat structure is formed. At this time, as the protective layer, a material which transmits the wavelength of the laser light 50 can be used.

The information display medium 200 shown in fig. 21 shows a structure in which a carrier layer 42 is further provided in addition to the structure shown in fig. 20. The carrier layer 42 facilitates the manufacturing process for forming the structure forming layer 10, the light reflecting layer 20, and the adhesive layer 40 when manufacturing the information display medium 200. Further, the information display medium 200 is also useful for the purpose of protecting the information display medium 200 when the information display medium 200 is attached to the base material 41.

The information display medium 200 shown in fig. 19, 20, and 21 is manufactured by, for example, sequentially forming the uneven structure and the flat structure, the light reflecting layer 20, and the adhesive layer 40 after forming the structure forming layer 10, but the order of forming may be changed according to the actual manufacturing process.

The interface on which the laser light 50 is incident is an interface (lower side in the drawing) opposite to the interface on which the uneven structure or the flat structure is formed, among the structure forming layer 10 in fig. 19, 20, and 21, but if the adhesive layer 40 and the substrate 41 are transparent materials or materials that transmit the laser light 50, the material forming the light reflecting layer 20 can be removed by causing the laser light 50 to enter from the interface on which the adhesive layer 40 is formed or the interface on which the substrate 41 is formed, thereby forming the 2 nd

information display regions

21 and 70.

Here, an adhesive layer may be formed on the back surface side of the

information display media

100 and 200, and a label may be formed by attaching a release paper.

[ method for producing information display Medium ]

Next, an example of a method for manufacturing the

information display media

100 and 200 will be described.

The

information display media

100 and 200 are manufactured, for example, by including the following steps 1 to 3 and performing the steps in this order.

Step 1 is a step of pressing a plate having a concave-convex structure and a flat structure formed in advance against the surface of the structure forming layer 10 to form a structure at the interface of the structure forming layer 10.

Step 2 is a step of forming the light reflecting layer 20 on the interface where the structure is formed in step 1.

The step 3 is a step of irradiating the structure forming layer 10 with the laser light while controlling the focal position of the laser light 50 from the interface where no structure is formed, thereby controlling whether or not the light reflecting layer 20 included in the 1

st region

30, 60 and the 2

nd region

31, 61 is removed, and forming the 2 nd

information display region

21, 70.

In this case, step 4 of forming the structure forming layer 10 on the support layer 42 may be provided before step 1.

Further, the method may include a step 4 of forming an adhesive layer 40 on the light reflecting layer 20 formed in the step 2, and a step 5 of bonding the light reflecting layer to the substrate 41 through the adhesive layer 40.

In step 3, the laser beam may be irradiated from the interface of the substrate 41 on the side not in contact with the adhesive layer 40 while controlling the focal position of the laser beam 50.

Fig. 20 shows a method of irradiating the

information display medium

100 or 200 with the laser light 50.

In this example, the laser light 50 emitted from the laser light source 52 passes through the mirror 53 and enters the

information display media

100 and 200 through the lens 51. Further, the order of passing from the mirror 53 and the lens 51 may be reversed. This enables the light reflecting layer 20 to be removed.

In fig. 22, the

information display media

100 and 200 are conveyed in the direction of the arrows in the figure. That is, the control of removing the light reflecting layer 20 by the laser light 50 can be realized during the conveyance of the

information display media

100 and 200.

The reflecting mirror 53 may be not only a normal plane mirror but also a galvanometer mirror, a micromirror array structure, or a liquid crystal display, and the irradiation position and phase of the laser beam can be controlled by controlling these mirrors with a computer. In addition, the focal position of the laser light can be controlled.

Further, when the reflecting mirror 53 has a micromirror array structure or a liquid crystal display, a plurality of focal positions can be formed by controlling the phase of the laser light 50. This can shorten the processing time of the actual manufacturing process.

As another method of controlling the focal position of the laser light 50, the focal position of the lens 51 can be controlled by controlling the position of the lens 51, or by using a liquid lens or a liquid crystal lens as the lens 51.

[ example of uneven Structure ]

Examples of the uneven structure formed in the 1

st regions

30 and 60 and the sub-region 62 include a relief structure shown in fig. 23 and a random dot structure shown in fig. 23.

The relief structure shown in fig. 23 is a 1-dimensional relief structure, and the grid vector thereof is parallel to the X direction, but may be parallel to the Y direction, and may be formed so as to be aligned in a direction forming a specific angle with the X, Y direction.

In addition, the relief structure may be a 2-dimensional relief structure. The relief structure in fig. 23 has a wave-like cross section, but may have a sawtooth wave, a square wave, or a step-like cross section. Alternatively, the shape may be any shape that conforms to a specific periodic function.

Here, the aspect ratio when the uneven structure is a periodic structure is determined by the structure period P1 and the structure depth (or height) D1. Specifically, the aspect ratio is calculated as the structure depth (or height) D1/structure period P1. Therefore, in order to achieve the effects of the present embodiment described above, the period, depth, and height of the relief structure need to be set for each sub-region 62.

As a relief structure having a specific periodic function, for example, a structure as shown in fig. 24 can be considered. Specifically, the periodic structure is a combination of a shallow structure and a deep structure. For the aspect ratio in this case, the aspect ratio is calculated from the width P2 of the structure forming the deepest structure and the structure depth (or height) D2.

As shown in fig. 24, when shallow structures and deep structures are periodically mixed in the sub-regions 62, the light reflection layer 20 is removed from the portion where the deep structures are formed, as described above. Accordingly, since the amount of removal of the light reflection layer 20 can be changed in the sub-region 62, the light reflection layer 20 can be gradually changed in the

information display medium

100 or 200 according to the aspect ratio of the uneven structure shape, and an intermediate gradation can be exhibited in the reflection observation or the transmission observation.

Further, since the region from which the light reflection layer 20 is removed can be set to be finer, a transmission type diffraction grating can be formed depending on the presence or absence of the light reflection layer 20, and information formed by diffracted light can be visually confirmed when the

information display media

100 and 200 are viewed in a see-through manner.

By forming the concave-convex structure as a convex structure as shown in fig. 23 and 24, reflection, diffraction, and absorption of light can be controlled. Information can be presented in the 1

st regions

30 and 60 by reflection, diffraction, and absorption of the light.

In the random dot structure shown in fig. 25, each dot is formed in a shape having an equal length in the X direction and the Y direction, but may be a shape that is long in the X direction or long in the Y direction. At this time, the lengths may be equal or random.

In addition, the cross-sectional shape of each point of the random point structure in fig. 25 is a quadrangle, but may be a semicircular shape, a semi-elliptical shape, a triangular shape, or a curved shape.

The aspect ratio of the random point formation depends on the formation width P3 and formation depth (or height) D3. Specifically, the aspect ratio is calculated as the structure depth (or height) D3/structure width P3. Therefore, in order to achieve the effect of the present disclosure as described above, it is necessary to set the width P3 and the depth of the random dot configuration, or the height D3, for each sub-region 62.

In the case where the random dot structure is a long shape in the X direction or the Y direction, the aspect ratio is calculated from the width in the short axis direction of the random dot structure and the structure depth or height.

In the random dot structure, when the lengths in the X direction and the Y direction are the same, light can be scattered non-directionally. In addition, when the light source is long in either the X direction or the Y direction, the light can be scattered in a direction orthogonal to the long direction to have directionality. Further, when there is a flat interface in which the cross-sectional shape of the random dot structure is a quadrangle and the Z direction is the normal direction, interference of light is likely to occur and color is likely to be developed. Information can be presented in the 1

st regions

30 and 60 by the scattering and interference of the light.

[ information display Medium combining Wet etching ]

This embodiment is similar to a so-called dry etching method in that the light reflecting layer 20 is removed by the laser beam 50. Unlike the current wet etching, the

information display media

100, 200 can be manufactured by all dry processes, and thus the manufacturing process cost can be reduced. However, it can also be combined with a wet process.

The light reflection layer 20 is removed by a wet process to form the 1 st information. The 1 st information is fixed patterns, marks, numbers, characters, geometric patterns, color pattern patterns and the like.

The light reflecting layer 20 can be formed by removing the light reflecting layer so as to form identification information according to the need by the dry process using the laser beam 50. The identification information includes a unique code, a personal portrait, a serial number, a specific symbol, and the like.

The information display medium 200 shown in fig. 26 includes a region 80 formed by a wet process, including the 1

st region

30, 60 and the 2

nd region

31, 61. Further, character information such as "good quality" is formed by the printing layer 90. Then, the 2 nd

information display regions

21 and 70 are formed by the manufacturing method of the present embodiment, and character information such as "1234 ABC" is formed as identification information.

In fig. 26, the identification information constituted by the 2 nd

information display areas

21 and 70 is information constituted by numerals and characters, but the identification information may be formed by a pattern, a symbol, a geometric pattern, or a color pattern. Further, the 2 nd

information display regions

21 and 70 may be formed across the region 80.

As described above, according to the

information display media

100 and 200 and the method of manufacturing the information display media of the present embodiment, the identification information constituted by the 2 nd

information display regions

21 and 70 from which the light reflection layer 20 has been removed is formed by irradiating the 1

st regions

30 and 60 and the sub-regions 62 forming these regions and the 2

nd regions

31 and 61 with the laser beam 50 and scanning the same, whereby information in which the 1 st information presented by the 1

st regions

30 and 60 and the 2 nd information presented by the 2 nd

information display regions

21 and 70 are superimposed can be provided. In addition, the identification information presented in the 2 nd

information display area

21, 70 can be formed as required.

As described above, it is possible to select whether or not the 2 nd

information display region

21 or 70 is formed in accordance with the focal position of the laser light 50 for the 1

st region

30 or 60 having the concave-convex structure or the 2

nd region

31 or 61 having the flat structure. In addition, whether or not the 2 nd

information display regions

21 and 70 are formed can be controlled by changing the removal amount of the light reflection film by modulating the aspect ratio of the uneven structure formed in the sub-region 62.

[ method of verifying information display Medium ]

The method for verifying an information display medium performs verification by irradiating a portion estimated to have identification information of the information display medium with pulsed laser light and presenting hidden information. The information presented by the irradiation may be photographed by a photographing device, and the identification information may be confirmed based on the photographed image. The authentication of the identification information presented by the irradiation can be performed, for example, by performing authentication.

Fig. 27 shows an authentication method of the

information display medium

100, 200.

As shown in fig. 27(a), the

information display media

100 and 200 are attached to the medium 250, and the geometric pattern and character information are formed by the print information 91. In the medium 250 shown in fig. 27(b), the 2 nd

information display regions

21 and 70 are formed by irradiating the medium 250 with pulsed laser light from the verifier 260, and character information such as "OK", that is, a state showing the appearance is presented.

Further, fig. 27(c) schematically shows an example of a state in which the medium 250 is inserted into the verifier 260 for verification.

In the

information display media

100 and 200, it is preferable that the information display media 250 have a plurality of sub-regions 62 in the 1

st region

30 and 60, and have a low-aspect-ratio uneven structure and a high-aspect-ratio uneven structure. Further, the information is presented by generating reflection, diffraction, refraction, interference, and scattering of light by the concave-convex structure constituting the plurality of sub-regions 62.

In addition, although a part of the light reflection layer 20 may be removed in advance from the

information display media

100 and 200, in this case, it is preferable to remove a region where the light reflection layer 20 is removed in advance by the verifier 260.

In this case, the

information display media

100 and 200 include the sub-region 62d, the sub-region 62d includes the uneven structure having a high vertical-to-horizontal ratio, and the light reflection layer 20 including the sub-region 62d having the uneven structure having a high vertical-to-horizontal ratio is removed by the laser beam 50 attached to the verifier 260, thereby forming the 2 nd

information display regions

21 and 70 and presenting information associated with the formation position of the sub-region 62 d.

By inserting the medium 250 into the verifier 260 and removing the light reflection layer 20 of the specific sub-area 62d in this manner, it is possible to display and confirm the hidden identification information indicating whether the medium 250 is a genuine product. The medium 250 presenting the hidden identification information can also be verified as being authentic by visually checking it, and the hidden information can be acquired and analyzed by the imaging device 261 incorporated in the verifier 260 in advance, thereby verifying whether it is authentic.

It is preferable that the hidden identification information indicating whether or not the medium 250 is a genuine product is not presented if the medium is not inserted into the verifier 260, and the hidden identification information is hidden by the 1 st information presented by the

information display media

100 and 200 before the medium is inserted into the verifier 260, and the identification information is designed or sized so as not to be visually confirmed.

In this way, the medium 250 including the

information display media

100 and 200 of the present disclosure can be used to introduce an authentication method in which the verifier 260 determines whether or not the medium 250 is authentic.

As described above, in the present embodiment, in the information display medium in which the uneven structure is formed, after the light reflection layer 20 is formed, the material for forming the light reflection layer 20 by the laser light is desirably removed, and the identification information can be formed so as to overlap with the 1 st information.

In addition, when the identification information is formed by removing the material by irradiating the laser light, even if the laser light irradiation is moved so as to straddle both the 1 st area and the 2 nd area, the identification information can be formed for the 1 st area or both the 1 st area and the 2 nd area as required by controlling the focal position of the laser light.

Further, the 1 st region is formed of 2 or more sub-regions adjacent to each other, and the amount of the material per unit area constituting the light reflection layer 20 of at least 1 sub-region of the sub-regions may be made smaller than the amount of the material per unit area constituting the light reflection layer 20 of the other sub-regions.

In this case, the amount of the material constituting the light reflection layer 20 can be modulated for each sub-region, and therefore, alignment of the optical expression based on the concave-convex structure and the optical expression based on light reflection obtained by modulating the amount of the material can be achieved, and a more complicated optical expression can be desirably formed.

The 1 st region includes a 1 st sub-region in which the uneven structure having an aspect ratio of 0.1 or more and less than 1 is formed and a 2 nd sub-region in which the uneven structure having an aspect ratio of 1 or more and less than 2 is formed, and the condensed pulse laser light is irradiated from the uncovered side of the light reflecting layer 20 within the structure forming layer so that a region having an average thickness of the structure forming layer is in a focal position, whereby the amount of the material per unit area constituting the light reflecting layer 20 in the 2 nd sub-region is less than or equal to 50%.

In this case, since the amount of the material constituting the light reflection layer 20 can be modulated according to the aspect ratio of the uneven structure forming the sub-regions, it is possible to achieve alignment of the optical expression based on the uneven structure and the optical expression based on light reflection obtained by modulating the amount of the material, and it is possible to form more complicated optical expressions as required.

In addition, at this time, the irradiation position of the laser light for forming the identification information may be made to pass through the plurality of sub-regions constituting the 1 st region, whereby the amount of the above-mentioned material constituting the light reflection layer 20 of the sub-regions is removed by 50% or more at the passing position. Alternatively, the irradiation position of the pulse laser light may be made to pass through the 1 st region and the 2 nd region, whereby the amount of the material constituting the light reflection layer 20 of the 1 st region and the 2 nd region may be removed by an amount of 50% or more at the passing position.

By decreasing the optical reflectance or increasing the transmittance of the region of the light reflection layer 20 from which 50% or more of the information display medium is removed, new information (identification information) can be displayed using the region of the light reflection layer 20 from which the new information is removed when the information display medium is viewed in reflection/transmission. Further, by modulating the amount of removal of the light reflecting layer 20, information having a gradation expression can be recorded. Moreover, the new display information can be processed as required.

Here, since the identification information is displayed in minute form using a minute character or the like and is formed to overlap with the 1 st display, it is possible to make it difficult to visually confirm the identification information in a normal state.

In the method for determining the authenticity of a medium to which an information display medium having identification information according to the present embodiment is added, for example, the medium is inserted into a verification device incorporating a pulsed laser beam, and a portion of the information display medium having identification information is irradiated with the pulsed laser beam, thereby presenting hidden information.

Alternatively, the identification information of the hidden state may be read and verified by an imaging device incorporated in the verification device.

This makes it possible to present information hidden in an information display medium having identification information and to confirm whether or not the medium is genuine.

As described above, the information display medium of the present disclosure can display a plurality of pieces of information in locally different regions when viewed in reflection, and therefore can be used as an optical effect for forgery prevention, and can be used as a forgery prevention medium that is embedded in or attached to an article such as a valuable paper such as a bank note or a commodity note, a certificate, a brand product, a high-priced commodity, an electronic device, or a personal authentication medium to protect the value and information included therein.

In addition, the present invention can be used for purposes other than forgery prevention, and can also be used as, for example, toys, learning materials, ornaments for commodities, posters, and the like.

In addition, since additional information can be added as needed, the present invention can be applied to addition of information that meets the need for a manufactured article and management of trace information. The information to be added is a QR code (registered trademark) or the like, and can be used in a machine authentication system using a reading device having an imaging function such as a camera, a mobile phone, or a smartphone.

Further, since the region where the light reflection layer 20 is removed can be defined according to the aspect ratio of the uneven structure, the light reflection layer 20 of the structure portion having a high aspect ratio can be removed by inserting the medium including the present disclosure into a specific device and irradiating the device with laser light, and whether or not a specific shape or information is presented can be confirmed by an imaging device inside the device or by visual observation, so that whether or not the medium is genuine can be confirmed and used in a machine authentication system or an authenticity judgment system.

Further, since the hidden information can be visually confirmed by perspective observation, the present disclosure can be used for purposes other than the above-described forgery prevention. For example, it can be used as a toy, a learning material, a decoration for a commodity, a poster, or the like.

"embodiment 3"

Next, embodiment 3 will be explained.

In the drawings, the same reference numerals are used throughout the drawings to designate the same or similar components that perform the same or similar functions, and redundant description thereof will be omitted.

The information display medium of the present embodiment includes an organic base material and a drawing portion formed on the organic base material. The drawing section includes one or both of a 1 st drawing section (rough drawing) and a 2 nd drawing section (fine drawing). The organic substrate is a substrate made of an organic material.

The organic material is organic resin, paper, etc. Examples of the organic material include acrylic resin, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, and parylene.

The 1 st drawing portion is formed by a combination of a removal portion formed by partially removing the surface of the organic base material and a carbonized recess portion formed by carbonizing the surface of the organic base material and having a lower light transmittance than the removal portion. The 2 nd drawing portion is formed by a combination of a void portion formed in the organic base material and a carbonized portion formed in the organic base material and having a lower light transmittance than the void portion. The 2 nd drawing section is formed to be finer than the 1 st drawing section.

For example, the organic substrate can be formed by a step of irradiating a pulsed laser beam having a small number of pulses focused near the surface of the organic substrate. For example, the carbonized recessed portion can be formed by a step of forming by irradiating a pulsed laser beam having a large number of pulses focused in the vicinity of the surface of the organic base material. The void portion can be formed by a step of forming by irradiating the organic base material with a pulsed laser having a small number of focused pulses. The carbonized part can be formed by a step of forming by irradiating the organic base material with a pulsed laser having a large number of pulses focused therein.

Further, for example, the information display medium of the present embodiment as described above can be embedded in or bonded to a substrate for securities to form securities.

Further, the information display medium may be provided with an adhesive layer and a release paper on the back side thereof to form a label.

Fig. 28 to 36 are partial cross-sectional views showing an example of an information display medium according to embodiment 3. Fig. 28 to 32 and 36 show partial cross-sectional views of the information display medium 100 in the case where the modified

regions

331, 332, and 333 are provided in the regions excluding the information display region, and fig. 33 to 35 show partial cross-sectional views of the information display medium 100 in the case where the modified region 331 is provided in the region including the information display region.

The applied region 330 is a portion where a drawn portion is formed, and the modified region is a portion where a removed portion, a carbonized recess, a void portion, or a carbonized portion is formed.

The information display medium 100 in fig. 28 includes an application region 330 to which energy is locally applied to the base material 10 made of a fiber material as an organic material, and the application region 330 includes a modified region 331.

In fig. 28, the modified region 331 is shown as being formed by cutting the substrate 10, but the modified region 331 may be formed by carbonizing, swelling, whitening, solidifying, or softening the surface of the substrate 10. When the material is carbonized, swollen, whitened, cured, or softened, the light transmittance is reduced as compared with the case of cutting.

The base material 10 is composed of a fiber raw material, and thus has an effect of scattering light. Further, the fiber raw materials are densely arranged, whereby an effect of transmitting light can be imparted to the base material 10. Further, the light transmittance of the base material 10 can be changed according to the arrangement density of the fiber raw material.

The substrate 10 may have a single-layer structure or a multi-layer structure. Further, a material having responsiveness may be added to the base material 10 by local energy application. Such as a thermochromic material having thermal responsiveness, a photochromic material having optical responsiveness, a fluorescent material, a phosphorescent material, a material having pressure responsiveness, a solvent-denatured material having solvent responsiveness, a material in which molecules are carbonized by applying energy, and the like. Further, the substrate 10 may be colored by adding a coloring material, a dye, or the like.

The base material 10 may be formed as a coarse fiber material in a manner of forming a watermark pattern of paper according to the prior art, or a part of the base material 10 may be removed.

As a method of forming the application region 330, for example, a method using a pulsed laser can be given. In addition, there may be a thermal head-based method, an electron beam-based method, an ion beam-based method, and the like.

In fig. 28, for example, a case where an application region 330 to which energy is locally applied is formed by a pulsed laser, and a modified region 331 which is a removed portion in a case where the substrate 10 is cut into a curved shape is formed is shown.

Fig. 29 shows a case where a reformed region 331a is formed as a removed portion in a case where the base material 10 is cut linearly.

The modified region 331 as a removed portion may be formed in a curved shape as shown in fig. 28, may be formed in a plurality of steps as shown in fig. 29, or may be formed of a single layer. The modified region 331 may be formed in a shape in which a curved line and a straight line are combined.

In addition, the substrate 10 may have a region where the modified region 331 is not formed.

The information display medium 100 in fig. 30 has a structure in which the base material 10 made of an organic material includes an application region 330 including a modified region 331.

Fig. 30 shows an example in which a removed portion is formed by cutting the base material 10 as the modified region 331. In this case, the light transmittance of the substrate 10 can be improved. For example, by changing the pulse number of the pulse laser beam irradiated to the substrate 10, the substrate 10 can be carbonized or swollen, whitened, solidified, and softened to form a carbonized concave portion. Also, a refractive index change may be generated in the modified region 331.

In fig. 31, the number of pulses of the pulse laser focused near the surface of the substrate is increased, and a carbonized recessed portion in which carbonization is achieved is formed as a modified region 331b of the surface.

In this case, the light transmittance of the base material is reduced as compared with the case of cutting the surface.

By comparing the removed portion and the carbonized recessed portion, a 1 st drawing portion having a drawing showing a shade can be provided.

Since the substrate 10 is made of an organic material, when the organic material has light transmittance, the substrate becomes a light-transmitting substrate.

In the base material 10, it may be formed in a coarse density of the organic material, a coarse density of the whitened area, a coarse density of the carbonized area, or the like by forming a watermark pattern. In addition, a portion of the substrate 10 may be removed.

Fig. 31 shows a case where a reformed region 331 in which the base material 10 is cut into a curved shape is formed in the application region 330. In addition, as in fig. 29, the reformed region 331 in the substrate 10 may be formed in a linear shape and a multi-layer cross-sectional shape, or may be formed of a single layer. The modified region 331 may be formed by a combination of curved lines and straight lines.

Fig. 32 shows an example in which the modified

regions

332 and 333 are formed inside the base material 10. The modified region 332 is a carbonized part, and the modified region 333 is a void part. The modified

regions

332 and 333 in fig. 32 show different modifications, and the same modification may be performed.

The positions where the modified

regions

332 and 333 are formed may be the same position in the thickness direction of the substrate 10 or may be different positions.

The region where the modified region 332 is formed and the region where the modified region 333 is formed may be formed to have different transmittances, for example. The modified

regions

332 and 333 may be formed not by the difference in light transmittance but by the difference in refractive index, scattering rate, reflectance, cloudiness rate, carbonization rate, and the like.

The substrate 10 may contain metal ions, and the metal fine particles may be formed as the modified regions 333 by locally applying energy to the inside of the substrate 10. Also, fine particles other than metal may be formed.

Further, the substrate 10 may have regions where the modified

regions

332 and 333 are not formed.

By comparing the carbonized part and the space, the 2 nd drawing part which presents the shade can be provided.

Fig. 33 shows a case where the information display region 340 is formed for the base material 10. In this example, the case where the modified region 331 is also formed in the information display region 340 is also shown. In practice, the modified region 331 may not be formed in the information display region 340, or the modified region 331 may be formed in a part of the information display region 340.

The modified region 331 formed in the information display region 340 shows a case where the information display region 340 is formed by cutting, but the information display region 340 may be formed by carbonization, swelling, whitening, curing, or softening. Also, a refractive index change may be generated in the modified region 331.

Fig. 34 shows a case where an information display region 341 is formed in the base material 10. The information display region 341 is formed by embedding and impregnating the base material 10 with a dye, ink, or the like. In addition, the information medium may be formed of a pigment, foil, or the like that is embedded when the substrate 10 is formed. Fig. 34 shows a case where the modified region 331 is also formed in the information display region 341. In practice, the modified region 331 may not be formed in the information display region 341, or the modified region 331 may be formed in a part of the information display region 341.

The modified region 331 formed in the information display region 341 shows a case where the information display region 341 is cut, but the information display region 340 may be carbonized, swollen, whitened, solidified, or softened. Further, no change in refractive index may be generated in the modified region 331.

Fig. 35 shows a case where the information display region 342 is formed in the interface on the side where the application region 330 and the modified region 331 are not formed with respect to the base material 10. When the substrate 10 has light transmittance, if the modified region 331 is formed at the interface opposite to the interface where the information display region 342 is formed, the information indicated by the information display region 342 can be observed through the modified region 331.

The information display region 342 and the modified region 331 may be formed in the same region or different regions.

When a part or all of the regions where the information display region 342 and the modified region 331 are formed coincide with each other, for example, the modified region 331 scatters information shown in the information display region 342, so that a part of the information can be hardly seen. The information displayed in the information display region 342 can be presented by enlarging or reducing the refractive index distribution in the modified region 331.

Fig. 36 shows a cross-sectional view of the case where the modified region 331 is formed at the interface of the base material and the modified

regions

332 and 333 are formed inside the base material in the base material 10 made of an organic material.

In fig. 36, the modified region (removed portion) 331 and the modified

regions

332 and 333 are formed at different positions, but may be formed at the same position.

Thus, heterogeneous drawing can be realized in the reformed region 331 (removed portion) formed in the interface (surface) of the substrate 10 and the reformed region 332 (void portion) formed in the substrate. The line width of the drawing by the removal portion is wider than that of the void portion. Therefore, the removed portion forms a slightly blurred image by drawing thicker than the void portion. On the other hand, the void portion is formed into a clear image by finer drawing than the removal portion. In this way, the removed portion and the void portion can enrich the gradation of drawing. Similarly, the line width drawn by the carbonized recessed portion and the carbonized portion can be changed similarly. The drawing of the carbonized recessed portion has a wider line width than that of the carbonized portion. Therefore, the carbonized recessed portion is drawn more coarsely than the carbonized part, and becomes a slightly blurred image. On the other hand, the carbonized part is formed into a clear image by a finer drawing than the carbonized concave part. Thus, the carbonized recessed portions and the carbonized portions can enrich the drawn color gradation.

Different information can be presented in each of the modified regions 331. The modified region 331 and the modified

regions

332 and 333 may be modified differently or may be modified identically.

The information display medium 200 shown in fig. 37 shows a case where the application region 330, the modified

regions

331, 332, and 333, the

information display regions

340, 341, and 342, and the watermark region 350 are formed on the base material.

In fig. 37, the application region 330, the modification regions 331, 32, and 33, and the

information display regions

340, 341, and 342 overlap each other, but may be formed independently of each other.

The information presented by the

information display regions

340, 341, and 342, the application region 330, and the

modification regions

331, 332, and 333 may or may not be formed so as to be aligned with each other.

Further, the application region 330 and the modification regions 331, 32, and 33 may be formed to overlap the watermark region 350.

Thus, the information displayed on the information display medium 200 can be formed into a plurality of pieces of information by the combination of each of the watermark region 350, the application region 330, and the

modification regions

331, 332, 333, and the

information display regions

340, 341, 342. In addition, the effects obtained will be described later.

In fig. 37, character information is presented in the application region 330, the

modification regions

331, 332, 333, and the

information display regions

340, 341, 342. Actually, the character information may be formed not only by character information but also by a specific shape such as a symbol, a geometric pattern, a pattern, or the like.

[ method for producing information display Medium ]

Next, a method for manufacturing the

information display media

100 and 200 will be described.

After the formation of the substrate 10, energy is locally applied to the interface or the interior of the substrate 10, and the substrate 10 is locally modified on the basis of a desired drawing pattern, thereby producing the

information display media

100 and 200.

Alternatively, after the formation of the substrate 10, the

information display medium

100 or 200 is manufactured by locally modifying the substrate 10 by providing an information display region and locally applying energy to the interface or the interior of the substrate 10.

After the formation of the substrate 10, the

information display media

100 and 200 can also be manufactured by locally modifying the substrate 10 by providing an information display region and locally applying energy to the interface or the interior of the substrate 10, and locally modifying the information display region by locally applying energy to the interface of the information display region.

As a method of locally applying energy to the substrate 10 and the

information display regions

340, 341, and 342, there is a method using a pulsed laser light source, a thermal head, an electron beam, and an ion beam. Further, a diagram in the case of using the pulsed laser light source 52 is shown in fig. 38.

The laser light emitted from the pulsed laser light source 52 passes through the lens 51 and is reflected by the mirror 53, and enters a specific position of the

information display medium

100, 200 in a focused manner on the

information display medium

100, 200 or a manufacturing line of the

information display medium

100, 200. Then, the energy of the laser light is locally condensed at the focal point to form the modified

regions

331 and 332.

In fig. 38, the laser light passes through the lens 51 and then the mirror 53, but the order may be reversed.

When the

information display media

100 and 200 are manufactured roll-to-roll during laser processing, the formation positions of the modified

regions

331 and 332 can be defined by controlling X, Y, Z, which is the focal position of the laser beam.

When the

information display media

100 and 200 are manufactured as a single sheet, the formation positions of the modified

regions

331 and 332 can be defined by moving the stage on which the

information display media

100 and 200 are installed or by controlling the position X, Y, Z of the focal point of the laser beam.

Alternatively, the reflecting mirror 53 has a micromirror array structure, and the focal position of the laser light can be controlled by controlling the micromirror array structure with a computer.

Further, by using the reflective mirror 53 as a reflective spatial light modulator and controlling the phase of each cell of the spatial light modulator by a computer, the focal position of the laser light can be controlled by controlling the phase of the laser light. Further, the spatial light modulator may be a transmissive structure.

Further, as the pulsed laser source 52, it is preferable that the pulse width is greater than or equal to 100 femtoseconds and less than or equal to 1 picosecond. Then, the laser light is instantaneously changed to a high energy state at the focal point by the lens 51, and the modified regions 331, 32, and 33 can be efficiently formed. In addition, the time in the high energy state is very short, and thus the influence is concentrated on the irradiation position.

As the pulsed laser source 52, any of a fiber laser, a solid-state laser, and a semiconductor laser using an optical fiber is preferably used. Examples of the solid-state laser include solid-state lasers using titanium sapphire crystal and YVO4 crystal. Also, the wavelength region of the pulsed laser source 52 is preferably in the near-infrared to infrared region.

The pulsed laser light source 52 can instantaneously generate a high energy state at the focal point of the laser light, and can process the base material 10 and the

information display regions

340, 341, and 342 with higher precision.

Fig. 39 shows a schematic diagram in the case where the pulsed laser source 52 locally applies energy to the substrate 10 or the

information display regions

340, 341, 342. The locality is preferably a dotted region as shown in fig. 39. This enables formation of more finely modified

regions

331, 332, 333.

Fig. 39(a) shows a case where the pulsed laser light 50 is focused on the interface of the base material 10, and fig. 39(b) shows a case where the pulsed laser light 50 is focused on the inside of the base material 10. Fig. 39(c) shows a case where focusing is achieved also in the vicinity of the interface at a position slightly away from the interface. Thus, by changing the focal position, the line width of the drawing can be changed, and the gradation of the drawing becomes rich.

In the energy converging portion 380 in fig. 39, the number of pulses of the pulsed laser beam is changed, whereby the carbonized part, the carbonized concave part, the removed part, and the void part can be selectively formed. When the number of pulses is high, the carbonized part and the carbonized recess are formed, and when the number of pulses is low, the removal or the void is formed. The number of pulses per second may be 10 to 50kHz, and for example, the number of pulses per second may be 10 to 1kHz when the removal part or the void part is formed, and the number of pulses per second may be 1k to 50kHz when the carbonized part or the carbonized recess part is formed.

Further, when the pulsed laser light source 52 is used, the modified

regions

331, 332, and 333 can be formed at high speed to form a pattern, and therefore high-speed processing can be achieved. In addition, by changing the pulse number, different modified regions can be formed, and various gradations and shades of images can be obtained, thereby realizing rich-expression images.

As described above, in the case of using the pulsed laser light source 52, high-precision processing and high-speed processing can be realized, and thus processing suitable for the

information display media

100 and 200 can be realized.

[ Observation method and Effect of information display Medium ]

From the above description, the effects described below and the observation method can be achieved by the present disclosure.

For example, when the information display medium 200 is viewed in a see-through manner in the modified

regions

331, 332, and 333 in which the thickness of the base material is reduced, character information can be viewed as a watermark using the modified

regions

331, 332, and 333, as shown in fig. 40.

As shown in fig. 41 and 42, the base material 10 is removed in the application region 370 with an extremely thin thickness, and the difference is not visually observed in the reflection observation, but the difference can be observed in the perspective observation. A latent image can be formed on the information display medium.

Further, as described above, the present disclosure can desirably realize high-speed and high-precision processing, and thus can form the

application regions

330, 370 and the modified regions 331, 32, 33 in accordance with the information display medium. Further, since the

information display areas

340, 341, and 342 formed in advance in the

information display media

100 and 200 can be processed as required in accordance with the design and information, more complicated information can be added to the

information display media

100 and 200.

In the processing using the pulsed laser light source 52, since the processing that meets the requirements for the information that can be visually observed as described above can be performed, and high-precision processing can be realized, the information that can be observed by enlarged observation can also be embedded in the information that can be visually observed.

Here, since the current formation of the watermark pattern is performed when the document sheet is used, a watermark pattern that meets the requirements cannot be formed. In addition, conventionally, in order to form a watermark pattern by laser processing, it is necessary to mix a pigment that absorbs a specific wavelength when used as a document paper, which raises a problem of cost increase.

Further, although a watermark pattern is currently used for a paper substrate, in recent years, since banknotes and the like using a polymer material composed of organic molecules as a substrate have started to be distributed, a method for forming a watermark pattern on a substrate composed of organic molecules cannot be established.

In contrast, in view of the above problems, the present disclosure provides an information display medium and a valuable paper capable of forming a watermark pattern on a substrate such as a paper substrate made of organic molecules as desired without using an additional material or the like, and an information display medium and a valuable paper capable of forming a watermark pattern on a substrate made of organic molecules as desired.

That is, according to the aspect of the present disclosure, it is possible to provide an information display medium and a valuable paper which can form a watermark pattern as desired on an organic substrate without using an additional material or the like, and an information display medium and a valuable paper which can form a watermark pattern as desired on a substrate made of organic molecules.

In addition, since the information display medium of the present disclosure can display a plurality of pieces of information in regions having different locality in reflection observation, it can be used as an optical effect for forgery prevention, and can be used as a forgery prevention medium for embedding or attaching to an article to protect contained value and information. Examples of the articles include securities such as bank notes and merchandise tickets, certificates, branded goods, high-priced goods, electronic devices, and personal authentication media.

Further, a label can be formed by forming an adhesive layer on the base material on which the printed layer of fluorescent ink and the hologram are formed.

In addition, since additional information can be added as needed, the present invention can be applied to addition of information that meets the need for a manufactured article and management of trace information. Further, by using the added information as the information code, the system can be used for a mechanical authentication system using a reading device having an imaging function such as a camera, a mobile phone, or a smart phone. As the information code, a QR code (registered trademark) can be exemplified.

Further, the present disclosure can visually confirm the hidden information by perspective observation, and therefore can be used for purposes other than the above-described forgery prevention. For example, it can be used as a toy, a learning material, a decoration for a commodity, a poster, or the like.

"embodiment 4"

Next, embodiment 4 will be described with reference to the drawings.

< information display Medium 100 >

The information display medium 100 of the present embodiment is an information display medium to which the forgery prevention means as shown in fig. 43 is applied.

The information display medium 100 is composed of a laminate in which a structure forming layer 10 constituting a support layer, a light reflecting layer 20, and a metal ion containing layer 412 are laminated in this order from the lower layer side toward the front surface side. The laminate may further have another layer such as an adhesive layer or a base layer as a lower layer, or may have another layer such as a surface protective layer on the metal ion-containing layer.

The information display medium 100 also includes the fine particles 413 in a partial region of the metal ion containing layer 412.

The structure forming layer 10 has light transmittance. The structure forming layer 10 may have a single-layer structure or a multi-layer structure. Further, the structure formation layer 10 may be formed of a material having optical anisotropy such as a liquid crystal material. Further, the resin may be colored by adding a pigment, a dye, or the like thereto.

As a material constituting the formation layer 10, a metal oxide or a mixture thereof can be used. The metal oxide is, for example, SiO₂(silica), TiO₂(titanium dioxide) and MgO (magnesium oxide). Also, the material constituting the formation layer 10 may be resin.

In addition, in the case where the structure formation layer 10 is formed of a metal oxide, it can be formed by, for example, a dry coating technique. The film can be formed by a wet coating technique such as gravure printing. Examples of the dry coating technique include evaporation, sputtering, and CVD (chemical vapor deposition).

In the case where the structure forming layer 10 is formed of a resin, it may be formed by, for example, a wet coating technique. Alternatively, the coating layer may be formed by a dry coating technique.

The thickness of the configuration forming layer 10 is preferably greater than or equal to 100nm and less than or equal to 5000 nm. By defining the thickness range, the uneven structure 414 described later is easily formed. In fact, the concave-convex structure 414 may have a thickness enough to be formed.

The structure formation layer 10 may have a uniform film thickness in the same region, or the film thickness may vary continuously or discontinuously.

Fig. 44 shows an example of the structure of the interface 10a with the light reflecting layer 20 in the structure forming layer 10. Fig. 44(a) shows an example of a region of the flat interface 10a in the structure forming layer 10, and fig. 44(b) shows an example of a region of the structure forming layer 10 in which the interface 10a having a relief structure (raster structure) periodically arranged in the 1-dimensional direction based on the concave-convex structure is formed.

The entire interface 10a between the structure formation layer 10 and the light reflection layer 20 may have a flat structure as shown in fig. 44(a), but the interface 10a in a partial region may have a concave-convex structure 414 as shown in fig. 44 (b).

The uneven structure 414 formed on the interface 10a of the structure forming layer 10 may be a relief structure (for example, a cross-grating structure), a random uneven-point structure, a random periodic relief structure (random grating structure), or the like, which is periodically arranged in the 2-dimensional direction, in addition to the relief structure arranged in the 1-dimensional direction shown in fig. 44 b. For example, when a relief structure or a cross-grating structure is formed, light is diffracted in the grid vector direction of the relief structure, and information can be presented by the diffracted light. In addition, when a random uneven point structure is formed, light is scattered, and information can be presented by using the scattered light. In addition, when the random grating structure is formed, light is particularly strongly scattered in the grid vector direction, and information can be presented by the scattered light having the directionality.

The structure forming layer 10 can exhibit a specific shape by forming the uneven structure 414 different from each other in each region in the planar direction. The specific shape is a pattern, a symbol, a numeral, a character, a geometric pattern, or the like.

In addition, the shape of the region where the uneven structure 414 is formed may exhibit the above-described specific shape.

The light reflection layer 20 may have a single-layer structure or a multi-layer structure.

As a material of the light reflection layer 20, for example, a metal or an alloy can be used. Examples of the metal include aluminum, silver, gold, copper, tin, and nickel. Examples of the alloy include steel, stainless steel, and duralumin. The light reflecting layer 20 may be made of a material having metallic luster such as titanium nitride.

Further, the material of the light reflection layer 20 may be a metal compound. As the metal compound, titanium dioxide (TiO) known as a high refractive index material can be exemplified₂) Zirconium dioxide (ZrO)₂) Tungsten oxide (WO)₃) Indium oxide (Y)₂O₃) Zinc oxide (ZnO), zinc sulfide (ZnS).

The light reflecting layer 20 is formed by, for example, a dry coating technique. Examples of the dry coating technique include evaporation, sputtering, and CVD (chemical vapor deposition). In addition, the light reflecting layer 20 may be formed using a wet coating technique.

The layer thickness of the light reflecting layer 20 is preferably 5nm or more and 100nm or less. More preferably 20nm or more and 60nm or less. By defining the layer thickness range, sufficient light reflectance can be obtained when the information display medium is visually observed, and the forgery prevention effect can be improved.

The light reflecting layer 20 may have a uniform film thickness in the same region, and the film thickness may be continuously or discontinuously changed. Also, a periodic configuration may be formed.

The light reflecting layer 20 may be formed in a specific shape such as a pattern, a symbol, a numeral, a character, a geometric pattern, or the like.

The metal ion-containing layer 412 is formed to include the fine particles 413 in a part or all of the region.

In fig. 42, a case where a plurality of fine particles 413 are arranged at a distance in a part of the region is illustrated, but the fine particles 413 may be arranged close to each other, or the fine particles 413 may be arranged in contact with each other. Preferably, a part or all of the fine particle-containing region is arranged so as to overlap with a region where a specific pattern of the structure formation layer 10 is formed in the thickness direction.

The metal ion-containing layer 412 is formed by dispersing a metal compound in a solvent with respect to a binder polymer material as a main material. Examples of the binder polymer material include polyvinylpyrrolidone and gelatin. Examples of the solvent include water and ethanol. Examples of the metal compound include silver nitrate and hydrogen tetrachloroaurate.

In forming the metal ion containing layer 412, it can be formed by, for example, a wet coating technique. After the coating, the metal ion containing layer 412 may be formed by baking.

The layer thickness of the metal ion containing layer 412 is preferably 500nm or more and 50000nm or less. More preferably 1000nm or more and 5000nm or less, as long as it can be formed by a wet coating technique.

The metal ion-containing layer 412 may have a uniform film thickness in the same region, or the film thickness may vary continuously or discontinuously. Also, a periodic configuration may be formed.

In addition, a specific pattern can be formed in the metal ion-containing layer 412 by arranging a plurality of fine particles. The specific pattern is, for example, a pattern, a symbol, a number, a character, a geometric pattern, or the like.

The fine particles 413 of the present embodiment are formed in the metal ion-containing layer 412 by reducing the metal ions contained in the metal ion-containing layer 412. Therefore, the material forming the fine particles 413 depends on the material contained in the metal ion containing layer 412. For example, in the case where silver nitrate is melted in the metal ion containing layer 412, silver ions are contained in the metal ion containing layer 412, and thus the obtained fine particles 413 are formed of silver. Hereinafter, a method of forming the fine particles 413 on the metal ion-containing layer 412 will be described.

The fine particles 413 formed in the metal ion-containing layer 412 can be set in a 3-dimensional region in the metal ion-containing layer 412, based on the 3-dimensional position at which the metal ions are reduced.

< other information display Medium 100 >

As shown in fig. 45, the other information display medium 100 is an example in which the uneven structure 414 is formed on the interface 10a of the partial region 421 of the structure formation layer 10, and the light reflection layer 20 and the metal ion containing layer 412 are formed thereon.

The information display medium 100 shown in fig. 45 is an example of a state before the fine particles 413 are formed in the metal ion containing layer 412, and the information display medium 100 shown in fig. 4 is formed by subjecting the metal ions contained in the metal ion containing layer 412 to a reduction treatment by a method described later with respect to the metal ion containing layer 412 of the information display medium 100 shown in fig. 45, in which the fine particles 413 are formed in the metal ion containing layer 412.

In the information display medium 100 shown in fig. 46, the uneven structure 414 is formed in a partial region of the structure forming layer 10. As described later, the light reflection layer 20 is partially removed, thereby forming a region where light is not reflected or light reflectance is greatly reduced. Hereinafter, a region where light is not reflected or light reflectance is greatly reduced is also referred to as a light low reflection portion 411B.

Thus, the information display medium 100 has: a region 420 in which the uneven structure 414 and the light reflecting layer 20 are formed; a region 21 in which the light low-reflection portion 411B is arranged; a region 422 in which the structure formation layer 10 is flat and the light reflection layer 20 is formed; and a region 423 in which the light low-reflection portion 411B is arranged.

As shown in fig. 46, the fine particles 413 are contained in the region of the metal ion containing layer 412 that overlaps the

regions

420 and 422.

The low light reflection portions 411B of the light reflection layer 20 in the

regions

421 and 423 are provided by partially coating a coating material constituting the light reflection layer 20.

In the example of fig. 46, the light low reflection portions 411B of the

regions

421 and 423 are provided after the light reflection layer 20 is once provided, and then removed by locally applying energy with laser light or the like. In addition, the light reflecting layer 20 can be removed by a chemical etching process.

By providing the

areas

421 and 423 having the light low reflection portion 411B, information obtained by the

areas

420 and 422 that do not easily reflect light can be seen more effectively in the light reflection layer 20. For example, since the uneven structure 414 is formed in the region 420, reflected, scattered, diffracted, interfered, or absorbed light can be visually observed through the uneven structure 414. On the other hand, in the region 421, since reflection of light is low, reflection, scattering, diffraction, interference, or absorption of the uneven structure 414 does not occur or occurs less. That is, visual information can be displayed depending on the presence or absence of the light reflecting layer 20.

In addition, the information presented by the concave-convex structure 414 in advance can be aligned with the position of the region 421 where the low light reflection portion 411B is provided. This makes it possible to present information on the uneven structure 414 to the observer in a more understandable manner. The same applies to the

regions

422 and 423 where the uneven structure 414 is not formed.

When the fine particles 413 are formed in the metal ion containing layer 412, reflection, scattering, diffraction, interference, or absorption of light is generated by the fine particles 413. For example, if the fine particles 413 are made of metal such as silver or gold, the incident light causes surface plasmon on the surfaces of the fine particles 413, and light of a specific wavelength is absorbed and scattered by the fine particles 413. The fine particles 413 are formed to be periodically arranged, and diffraction and scattering of light are generated. When the formed fine particles 413 are formed continuously adjacent to or in contact with each other, light is reflected. Therefore, the fine particles 413 can realize an optical phenomenon different from the optical phenomenon caused by the uneven structure 414.

The following description is made on the premise that the fine particles 413 are made of a metal material, surface plasmons are generated by the fine particles 413, and light of a specific wavelength is absorbed and scattered by the fine particles 413 to develop color.

By providing the

areas

421 and 423 provided with the light low-reflection portion 411B, information obtained by the

areas

420 and 422 where the light reflection layer 20 is not removed can be seen more effectively. For example, since the uneven structure 414 is formed in the region 420, light reflected, scattered, diffracted, interfered, or absorbed by the uneven structure 414 can be visually observed. On the other hand, in the region 421, the reflection of light is low, and reflection, scattering, diffraction, interference, or absorption does not occur or occurs to a small extent due to the uneven structure 414. That is, visual information can be displayed depending on the presence or absence of the light reflecting layer 20.

In addition, the information presented by the concave-convex structure 414 in advance can be aligned with the position of the region 431 of the light low-reflection portion 411B. This makes it possible to present information on the uneven structure 414 to the observer in a more understandable manner. The same applies to the regions 432 and 433 where the uneven structure 414 is not formed.

On the other hand, the color development of the fine particles 413 formed in the metal ion-containing layer 412 can be observed in any region. Therefore, for example, information of the uneven structure 414 in the region 420 and the color development of the fine particles 413 can be visually observed at the same time.

In this way, in addition to information obtained by the presence or absence of the uneven structure 414 or the presence or absence of the light reflecting layer 20, the fine particles 413 are formed, whereby further information can be added.

Further, by using a method for forming the fine particles 413 described later, the region where the fine particles 413 are formed and the region where the light reflection layer 20 is removed (the light low reflection portion 411B) can be formed in a good alignment in one process. Accordingly, various combinations can be realized depending on the presence or absence of the light reflecting layer 20, the presence or absence of the uneven structure 414, and the presence or absence of the fine particles 413, and therefore, more complicated information presentation can be realized, and the appearance of the information display medium 100 can be improved.

< information display Medium 200 >

Fig. 47 shows an example of the information display medium 200. In the following description, a case of using a metal material as the light reflection layer 20 is assumed.

In fig. 47, the uneven structure 414 is not formed in the structure forming layer 10, and a pattern in which 3 diamonds are connected is formed by the region 450 in which the light reflecting layer 20 is formed and the region 451 in which the light low reflecting portion 411B is formed. Further, a region 452 in which the uneven structure 414 is formed has a roman letter "a", a region 453 formed by the uneven structure 414 and the fine particles 413 has a roman letter "B", and a region 454 in which only the fine particles 413 are formed without the uneven structure 414 has a roman letter "D". Finally, the "C" of the roman alphabet and the cut edge pattern in which 3 diamonds are connected are formed in the

pattern regions

455 and 456 by a method (a method of forming the fine particles 413) described later in the manufacturing method. In the region 456, the fine particles 413 are formed on the metal ion-containing layer 412.

In the region 450, light reflected by the light reflecting layer 20 can be visually observed, and in the region 451, the structure forming layer 10 can be observed. Here, for example, when the information display medium 200 is attached to a base material via a transparent adhesive or the like, information formed in advance on the base material can be visually observed in the region 451. In this case, the adhesive may be colored.

In the region 452, in the case where the uneven structure 414 is, for example, a grating structure, since light is diffracted by the roman alphabet "a", the roman alphabet "a" is seen so that a rainbow color changes when visually observed, and information can be obtained.

In the region 453, when the uneven structure 414 has a grating structure as in the region 452, the roman alphabet "B" is seen so that the rainbow color changes. Further, when there is color development by the fine particles 413, the rainbow color change by the uneven structure 414 and the color development by the fine particles 413 are mixed, and color expression different from that of the region 452 can be realized.

In the region 454, the colored reflected light can be visually observed by the color development of the fine particles 413 with respect to the light reflected by the light reflection layer 20. For example, when aluminum is used as the light reflection layer 20, the region 454 shows a golden gloss when visually observed in the case where the color development by the fine particles 413 is yellow.

In the region 455, the light reflection layer 20 is removed in such a manner that the "C" of the roman alphabet is displayed, and the "C" of the roman alphabet can be visually observed.

In the region 456, the light reflection layer 20 is removed, and at the same time, the fine particles 413 abut against the region, so that a colored cut pattern can be observed visually.

As described above, the light reflection layer 20 and the fine particles 413 are locally formed in each region, whereby a plurality of pieces of information can be added to one information display medium 200. In addition, since the fine particles 413 are formed after the uneven structure 414, the light reflecting layer 20, and the metal ion containing layer 412 are formed, and the light reflecting layer 20 can be removed, information can be added by post-processing.

< method for manufacturing information display Medium >

Next, a method of manufacturing the

information display media

100 and 200 will be described.

The

information display media

100 and 200 are manufactured, for example, through the following steps (1) to (5). (1) First, the uneven structure 414 is formed on the structure formation layer 10, and the light reflection layer 20 is formed.

(2) Then, the light reflecting layer 20 is partially removed to form a low light reflecting portion.

(3) Then, the metal ion-containing layer 412 is provided to form a laminate.

(4) Then, energy is locally applied to the metal ion-containing layer 412 of the laminate, thereby reducing the metal ions in the metal ion-containing layer 412 and forming fine particles 413 in the metal ion-containing layer 412.

(5) Then, energy is locally applied to the light reflection layer 20 to remove the light reflection layer 20.

The

information display media

100 and 200 are manufactured by the above processes. In the above-described production method, (2) and (5) are not essential for production, and may be carried out as needed.

As a method of locally applying energy to the metal ion containing layer 412, there is a method using a pulsed laser light source or a thermal head. Further, a diagram in the case of using a pulsed laser light source is shown in fig. 48.

That is, the laser light 50 emitted from the pulsed laser light source 52 passes through the lens 51 and is reflected by the mirror 53, and enters the metal ion containing layer 412 forming the

information display media

100 and 200 so as to be focused. Then, the energy of the laser beam is locally focused at the focal point, and the metal ions are reduced by the energy to form the fine particles 413 at the focal point.

Then, if the laser beam 50 is focused on the light reflecting layer 20, the light reflecting layer 20 is removed by the energy locally condensed, and a layer in a low reflection state is formed. This technique is known as laser ablation.

In addition, for example, when the structure forming layer 10 is brought into focus by the laser light 50, the structure forming layer 10 can be removed at this position.

When the laser beam 50 is processed, the region where the fine particles 413 are formed and the region where the light reflection layer 20 is removed can be selected by controlling the installation position of the

information display media

100 and 200 or the X, Y, Z of the focal point of the laser beam 50.

Alternatively, the mirror 53 has a micromirror array structure, and the focal position of the laser light 50 can be controlled by controlling the micromirror array structure with a computer, while controlling the phase of the laser light 50.

By the above-described manufacturing method, the fine particles 413 can be formed in the metal ion containing layer 412, and a part of the region of the light reflecting layer 20 can be removed. Further, the region where the fine particles 413 are formed and the region where the light reflection layer 20 is removed may be the same.

Since the above-described manufacturing method can be applied after the

information display media

100 and 200 are formed, the method can be applied as a post-processing method for a manufacturing line of the

information display media

100 and 200. Therefore, by using the manufacturing method of the present disclosure, processing to the

information display media

100 and 200 can be performed as required.

In this way, if the manufacturing method of the present disclosure is applied to the

information display media

100 and 200, different optical expressions can be realized in the

respective regions

450, 451, 452, 453, 454, 455, and 456, and different pieces of information can be provided. By the combination of the optical expressions and the combination of the information, it can be determined that the

information display media

100 and 200 are genuine products.

(Effect and others)

The information display medium of the present embodiment is composed of a laminate in which a support layer that transmits light, a light reflection layer, and a metal ion-containing layer are laminated in this order, the light reflection layer and the metal ion-containing layer are in contact, and fine particles are contained in a partial region of the metal ion-containing layer.

In this case, the light reflecting layer is locally disposed on the same plane, and the region of the metal ion-containing layer containing the fine particles and the region provided with the light reflecting layer are disposed so as to have an overlapping portion in the thickness direction of the laminate.

The region of the metal ion-containing layer containing the fine particles and the region provided with the light-reflecting layer may be arranged so as to be aligned and superposed in the thickness direction of the laminate.

The light-reflecting layer may be a laminate in which a structure is formed at an interface between the support layers, the structure-forming layer is in contact with one surface of the light-reflecting layer, the other surface of the light-reflecting layer is in contact with the metal ion-containing layer, the metal ion-containing layer contains fine particles in a partial region, the light-reflecting layer is locally provided at the interface in contact with the structure-forming layer, and the structure-forming layer has a concave-convex structure at a part of the interface in contact with the light-reflecting layer.

In addition, at least 2 regions out of the region containing the fine particles, the region provided with the light reflection layer, and the region provided with the uneven structure of the metal ion-containing layer are arranged so as to have an overlapping portion in the thickness direction of the laminate.

The light reflecting layer is made of, for example, a metal material or a metal oxide material.

In the method for producing an information display medium, the fine particles are formed in the metal ion-containing layer by locally applying light energy to the metal ion-containing layer after the laminate is provided.

In the method for manufacturing the information display medium, after the laminate is provided, energy is locally applied to the light reflection layer, thereby locally forming a region where light is not reflected or light reflectance is low with respect to a layer position of the light reflection layer.

With such a configuration, the fine particles are contained in a partial region of the metal ion-containing layer that transmits light on the front surface side, and thus it is possible to make it difficult to forge a display pattern formed on the lower layer.

Further, if necessary, the fine particles may be arranged in a 3-dimensional specific pattern, and an information display pattern may be formed in the metal ion-containing layer.

Further, since the metal ion-containing layer or the light reflecting layer can be processed as required without adding a material or the like, authentication information, identification information, a decorative pattern, or the like can be added to each region. Further, since the processing for forming fine particles and the processing for the light reflecting layer can be performed simultaneously, either the processing for aligning the respective positions or the processing for not aligning the positions can be performed.

In addition, the information display medium of the present disclosure can display a plurality of pieces of information in regions having different locality when viewed in reflection, and therefore can be used as an optical effect for preventing forgery. Therefore, the present invention can be used as a forgery prevention medium for protecting value and information included in articles such as securities, certificates, branded goods, high-priced goods, electronic devices, and personal authentication media.

Further, the present invention can be used for purposes other than forgery prevention, and can also be used as a toy, a learning material, an ornament of a commodity, a poster, and the like.

"embodiment 5"

Next, embodiment 5 will be described in detail with reference to the drawings.

[ information display Medium ]

Fig. 49 is a partial sectional view of an information display medium according to embodiment 1 of embodiment 5, and the information display medium 100 is an information display medium to which an anti-counterfeit means is applied.

The information display medium 100 includes an information display region 560 (see fig. 60) inside a base material 10 made of a light-transmitting organic material.

Here, the substrate 10 is formed of, for example, an organic resin having light transmittance. Examples of the light-transmitting organic material resin include acrylic resins, polyethylene terephthalate, polycarbonate, polyethylene naphthalate, and parylene. The substrate 10 may have a single-layer structure or a multi-layer structure. The substrate 10 may be made of a material having optical anisotropy, such as a liquid crystal material. Further, the base material 10 may be colored by adding a dye or the like to the resin.

In addition, a material having responsiveness may be added to the base material 10 by locally applying energy. For example, a thermochromic material having thermal responsiveness, a photochromic material having optical responsiveness, a fluorescent material, a phosphorescent material, a material having pressure responsiveness, a solvent-denatured material having solvent responsiveness, a material in which molecules are carbonized by applying energy, or the like. Further, the substrate 10 may contain metal ions.

When the organic material resin polymer material is used as the substrate 10, it can be formed by, for example, a wet coating technique. Alternatively, the coating layer may be formed by a dry coating technique.

The substrate 10 may be formed as a single body, or the substrate 10 may be formed by coating a carrier film or the like.

The substrate 10 has light transmittance, and information can be presented by the substrate 10 itself. For example, by providing a relief hologram structure, a light scattering structure, a light interference structure, or the like, information can be recognized upon visual observation by utilizing optical effects based on these structures.

The thickness of the substrate 10 is preferably 5 μm or more and 200 μm or less. More preferably 20 μm or more and 150 μm or less. By providing such a thickness, the strength necessary for processing the inside of the substrate 10 is obtained.

In the information display medium 100 in fig. 49, 2 continuous modified

parts

521a and 521b are provided inside the base material 10.

Here, each of the continuous modified

portions

521a and 521b is formed by continuously forming the modified portion 520 having properties different from those of other regions so that a part or all of the modified portions 520 adjacent to each other in the substrate 10 overlap each other, and an interface 530 with the unmodified region 511 is formed in a continuous curved surface shape.

The interface 530 functions as an optical interface, and displays information in the information display area 560 according to the curved surface shape thereof.

Here, energy is locally added to the inside of the substrate 10 to form the modified portion 520 in the energy applying portion inside the substrate 10. For example, the modified portion 520 is formed by subjecting the substrate 10 to refractive index change, removal, carbonization, swelling, whitening, curing, and softening.

Examples of a method for forming the modified portion 520 include a method using a pulsed laser. In addition, a thermal head method, an electron beam method, an ion beam method, or the like may be used.

Here, the curved surface shape of the interface 530 formed by one continuous modified portion 521a is a curved surface shape represented by a periodic function, and is formed by a repeated pattern.

In this way, the curved surface shape of the interface 530 is a curved surface shape expressed by a periodic function to form a diffraction grating structure, and information is formed in the information display area 560 by diffracted light diffracted by the diffraction grating structure.

Further, the curved surface shape of the interface 530 may be a curved surface shape represented by an overlap function based on 2 or more periodic functions. The curved surface shape of the interface 530 may be a curved surface shape expressed not by a periodic function but by an overlap function, as long as it is a curved surface.

The curved surface shape of the interface 530 formed by the other continuous modified portion 521b is a curved surface shape in which steps having different heights are formed in the film thickness direction of the substrate 10 among the curved surface shapes expressed by the periodic function. As a result, a diffraction grating structure is formed, and information is displayed in the information display area 560 by diffracted light diffracted by the diffraction grating structure.

Next, an information display medium according to embodiment 2 of embodiment 5 will be described with reference to fig. 50.

The basic configuration of the information display medium 100 shown in fig. 50 is the same as that of the information display medium 100 shown in fig. 49, but the continuously modified portion 521 is formed of 1, and the curved surface shape of the interface 530 between the non-modified region 511 and the continuously modified

portions

521a and 521b of the continuously modified portion 521 is different from the curved surface shape of the interface 530 between the non-modified region 511 and the continuously modified

portions

521a and 521b of the information display medium 100 shown in fig. 49.

That is, in the information display medium 100 shown in fig. 50, the curved surface shape represented by a periodic function of the curved surface shape of the interface 530 with the unmodified region 511 of the continuously modified portion 521 is a fresnel lens shape inside the substrate 10. That is, the curved surface shape forms a specific free-form surface structure in which fresnel formation is realized inside the base material 10. Thus, information is displayed in the information display area 560 by the reflected light reflected by the specific fresnel-formed free-form surface structure. In addition, an optical pseudo-stereoscopic effect can be added in the reflection observation.

Next, an information display medium according to embodiment 3 of embodiment 5 will be described with reference to fig. 51.

The basic configuration of the information display medium 100 shown in fig. 51 is the same as that of the information display medium 100 shown in fig. 49, but differs in that the information display medium is not a continuously modified

part

521a or 521b but a discontinuously modified part 522 provided inside the base material 10.

Here, the discontinuous modified portion 522 is formed by discontinuously forming the modified portions 520 so that adjacent modified portions 520 do not overlap in the inside of the substrate 10, and is formed in a continuous curved surface shape at the pseudo interface 531 of the unmodified region 511.

The simulation interface 531 functions as an optical interface, and displays information in the information display area 560 by using the curved surface shape thereof.

The curved surface shape of the simulation interface 531 is a curved surface shape expressed by a periodic function, and is formed by a repetitive pattern. In this way, the curved surface shape of the simulation interface 531 is a curved surface shape expressed by a periodic function, thereby forming a diffraction grating structure, and information is displayed in the information display area 560 by diffracted light diffracted by the diffraction grating structure.

Next, an information display medium according to embodiment 4 of embodiment 5 will be described with reference to fig. 52.

The basic configuration of the information display medium 100 shown in fig. 52 is the same as that of the information display medium 100 shown in fig. 51, but differs in that the curved surface shape of the simulation interface 531 is a curved surface shape represented by an overlapping function of a plurality of periodic functions.

Thus, the curved surface shape of the simulation interface 531 is a curved surface shape represented by an overlap function of a plurality of periodic functions to form a diffraction grating structure, and information is displayed in the information display area 560 by diffracted light diffracted by the diffraction grating structure. The optical effect is easily produced by setting the curved surface shape of the simulation interface 531 to a curved surface shape represented by an overlapping function of a plurality of periodic functions.

Next, an information display medium according to embodiment 5 of embodiment 5 will be described with reference to fig. 53.

The basic configuration of the information display medium 100 shown in fig. 53 is the same as that of the information display medium 100 shown in fig. 51, and differs in that the curved surface shape of the simulation interface 531 is a lens shape.

Thereby, information is displayed in the information display area 560 by the reflected light reflected by the lens shape. In addition, an optical pseudo-stereoscopic effect can be added in the reflection observation.

Next, an information display medium according to embodiment 6 of embodiment 5 will be described with reference to fig. 54.

The basic configuration of the information display medium 100 shown in fig. 54 is the same as that of the information display medium 100 shown in fig. 51, but differs in that the curved surface shape of the simulation interface 531 is a fresnel lens shape.

Thereby, information is displayed in the information display area 560 by the reflected light reflected by the fresnel lens shape. In addition, an optical pseudo-stereoscopic effect can be added in the reflection observation.

The simulated interface 531 in fig. 54 shows the fresnel lens shape, but may be an interface shape obtained by intermittently cutting a free-form surface shape. In this case, an optical pseudo-stereoscopic effect corresponding to the free-form surface shape can be added in the reflection observation.

When the continuous modified

portions

521a, 521b, 521 formed by forming the modified portion 520 in an overlapping manner are formed as in 1 to 2 of embodiment 5, or when the discontinuous modified portion 522 formed by forming the modified portion 520 in a non-overlapping manner is formed as in 3 to 6 of embodiment 5, the position in the film thickness direction of the substrate 10 on which the modified portion 520 is formed may be random. This causes scattering of light incident on the substrate 10, and information can be displayed according to the shade and orientation of the scattered light. That is, the interface 530 or the pseudo interface 531 has a curved surface shape to form a light scattering structure, and information can be displayed in the information display area 560 by scattered light scattered by the light scattering structure.

Further, by changing the density of the formation-modified portion 520, the continuous modified

portions

521a, 521b, 521, or the discontinuous modified portion 522, the intensity of the scattered light of the light incident on the base material 10 can be modulated, and information can be displayed according to the intensity.

Next, an information display medium according to embodiment 7 of the present disclosure will be described with reference to fig. 55.

In the information display medium 100 shown in fig. 55, a plurality of continuous modified portions 521 according to

embodiments

1 and 2 are continuously formed at a predetermined formation pitch P along the y-axis direction in the substrate 10 to form modified regions 523.

At this time, when light is made incident on the information display medium 100 at an incident angle θ in, diffracted light generated by the diffraction grating structure formed by the interface 530 conforms to the following expression (1).

P(sinθ_in－sinθ_diff)＝mλ…(1)

Here, P is a diffraction grating formation pitch, θ in is an incident angle, θ diff is a diffraction angle, m is a number of orders formed of an integer, and λ is a wavelength of incident light or diffracted light.

As can be seen from equation (1), the characteristics of the diffracted light are influenced by the diffraction grating formation pitch P.

Actually, by forming the modified region 523 with the formation pitch P of the continuous modified portion 521 being locally changed, diffracted light having different wavelengths or diffracted light having different diffraction angles can be observed in each portion due to the difference in the formation pitch P when the information display medium 100 is observed, and information can be displayed thereby.

Further, even if the pitch is not periodically formed, a phase hologram structure for controlling the phase difference of incident light can be formed by using the interface 530 including the continuous modified portion 521b shown in fig. 49 and the pseudo interface 531 including the discontinuous modified portion 522 including the modified portion 520 shown in fig. 52. This makes it possible to form a computer hologram structure in which the diffraction image, which is currently called a kinoform, is bright, and to obtain a three-dimensional optical expression by the dot-shaped modifying portions 520.

Further, since the modifying section 520 is formed on the substrate 10 so as to be controllable in the film thickness direction, interference fringes that currently form a volume hologram structure can be formed by the modifying section 520. Thereby, a three-dimensional optical expression can be obtained by the modifying portion 520.

Further, by forming the outer shape of the modified portion 520 or the continuous modified portion 521 in a multilayer shape and forming a cross section such as a sawtooth wave in a pseudo manner, a blazed diffraction grating structure can be formed and diffracted light brighter than the current state can be obtained.

Next, an information display medium according to embodiment 8 of embodiment 5 will be described with reference to fig. 56.

The information display medium 100 shown in fig. 56 has a modified region 523 formed by forming a plurality of continuous modified parts 521 at a predetermined formation pitch P in the substrate 10 according to

embodiments

1 and 2, and a pseudo interface 532 formed by an interface 530 between the continuous modified parts 521. Thus, as described above, a diffraction grating structure based on the simulation interface 532 can be formed, and information can be displayed using the diffracted light generated thereby.

In the information display medium 100 shown in fig. 56, the continuously modified portion 521 is formed so as to draw a curve inside the substrate 10, but may be a straight line or a combination of a straight line and a curve. Further, the film can be formed while changing the film thickness direction of the substrate 10. This enables a more complex diffraction grating structure to be formed.

As the information display medium 100 shown in fig. 56, the continuous modified portion 521 is formed so as to draw a curve, so that parallax can be generated when a person visually observes the diffracted light formed by the simulated interface 532. This allows information obtained by diffracting light to be optically expressed in a three-dimensional manner.

Fig. 57 shows an information display medium according to embodiment 5 or 9.

The information display medium 100 shown in fig. 57 has a modified region 523 formed by forming a plurality of discontinuous modified portions 522 in embodiments 3 to 6 at a predetermined formation pitch P in the substrate 10, and a pseudo interface 532 formed by the pseudo interface 531 of each discontinuous modified portion 522. This allows a diffraction grating structure to be formed by the simulation interface 532, and information to be displayed by the diffracted light generated thereby.

[ method for producing information display Medium ]

Next, a method for manufacturing the information display medium 100 will be described.

The information display medium 100 is manufactured by performing the following process.

A step of locally applying energy to the inside of the substrate 10 after the substrate 10 is formed, thereby locally forming the modified part 520,

the step of forming the modified portion 520 is continuously repeated in accordance with a previously designed pattern.

That is, the information display medium 100 according to

embodiment

1 and 2 is manufactured by a method including the steps of: a step of locally applying energy to the inside of the substrate 10 to form a modified part 520 having a property different from that of other regions in the energy application part inside the substrate 10; and a step of continuously forming the modified portions 520 so that a part or all of the adjacent modified portions 520 overlap each other inside the substrate 10, thereby forming a continuous modified portion 521 in which an interface 530 with the unmodified region 511 is formed into a continuous curved surface shape.

The information display medium 100 according to embodiments 3 to 6 of embodiment 5 is manufactured by a method including the steps of: a step of locally applying energy to the inside of the substrate 10 to form a modified part 520 having a property different from that of other regions in the energy application part inside the substrate 10; and a step of forming the modified parts 520 discontinuously in the substrate 10 so that the adjacent modified parts 520 do not overlap each other, and forming the discontinuous modified parts 522 in which the pseudo-interfaces 531 of the non-modified regions 511 are formed in continuous curved surface shapes.

As described above, the information display medium 100 according to embodiment 7 of embodiment 5 is manufactured by forming the continuous modified portion 521 in the substrate 10 and forming the modified region 523 by continuously forming the plurality of continuous modified portions 521 at the predetermined forming pitch P in the predetermined direction.

As described above, the information display medium 100 according to embodiment 8 of embodiment 5 is manufactured by forming the continuous modified portion 521 inside the base material 10, continuously forming the plurality of continuous modified portions 521 at the predetermined forming pitch P along the predetermined setting direction, and forming the modified region 523 in which the dummy interface 532 is formed by the interface 530 of each continuous modified portion 521.

As described above, the information display medium 100 according to embodiment 9 of embodiment 5 is manufactured by forming the discontinuous modified portions 522 in the substrate 10, forming the plurality of discontinuous modified portions 522 at the predetermined formation pitch P, and forming the modified regions 523 in which the pseudo interfaces 532 are formed by the pseudo interfaces 531 of the discontinuous modified portions 522.

In the method of manufacturing the information display medium 100 according to embodiments 1 to 9 of embodiment 5, 2 or more modified parts 520 are simultaneously formed in the substrate 10. This can shorten the process time for forming the continuous modified portion 521, the discontinuous modified portion 522, and the modified region 523.

Here, as a method of locally applying energy to the base material 10, there is a method using a pulsed laser light source, a thermal head, an electron beam, or an ion beam. Further, a diagram in the case of using the pulsed laser light source 52 is shown in fig. 58.

The laser light 50 emitted from the pulsed laser light source 52 passes through the lens 51 and is reflected by the mirror 53, and is made incident in focus on the information display medium 100 or a specific position of the information display medium 100 on the manufacturing line of the information display medium 100. Then, the energy of the laser light 50 is locally condensed at the focal point to form a point-like modified portion 520.

In fig. 58, the laser light 50 passes through the lens 51 and then the mirror 53, but the order may be reversed.

When the information display medium 100 is manufactured by a roll-to-roll method in processing with the laser light 50, the formation position of the modifying section 520 can be selected and controlled by controlling the focal position (the position in the x direction, the y direction, and the z direction) of the laser light 50.

When the information display medium 100 is manufactured in a single sheet, the formation position of the modifying unit 520 can be selected and controlled by moving a stage on which the information display medium 100 is mounted or by controlling the focal position (the position in the x direction, the y direction, and the z direction) of the laser beam 50.

Alternatively, the reflecting mirror 53 may have a micromirror array structure, and the focal position of the laser light may be controlled by controlling the micromirror array structure with a computer.

Further, the mirror 53 may be a reflective spatial light modulator, and the phase of each cell of the spatial light modulator may be controlled by a computer, whereby the phase of the laser light may be controlled to control the focal position of the laser light. The spatial light modulator may be of a transmissive type.

Further, as the pulsed laser source 52, it is preferable that the pulse width is greater than or equal to 100 femtoseconds and less than or equal to 1 picosecond. This allows the laser beam 50 to pass through the lens 51 and instantaneously reach a high energy state at the focal point, and the modified portion 520 can be efficiently formed. In addition, the time of the high energy state is very short, and therefore, there is no influence except the irradiation position.

As the pulsed laser source 52, it is preferable to use either a fiber laser using an optical fiber or a solid laser using a titanium sapphire crystal. Also, the wavelength region of the pulsed laser source 52 is preferably in the range of the near infrared to infrared region.

By using the pulse laser source 52, a high-energy state can be instantaneously formed at the focal point of the laser beam, and higher-definition processing can be performed on the substrate 10.

Fig. 59 is a schematic view showing a case where the pulsed laser source 52 locally applies energy to the base material 10 to form the energy application portion 500. As shown in fig. 59, the local representation is that energy passing through the lens 51 is applied in a dot shape. This enables formation of a more refined modified portion 520.

In addition, when the pulsed laser light source 52 is used, the modified portion 520 can be formed at high speed to realize patterning, and thus high-speed processing can be realized.

As described above, since high-precision processing and high-speed processing can be realized by using the pulsed laser light source 52, processing suitable for the

information display media

100 and 200 can be realized.

As a conventional method for forming a hologram, there is known a method in which a plate having a fine uneven structure for forming a hologram formed thereon is pressed against a resin material to imprint the fine uneven structure on the resin material. The hologram is manufactured by the embossing process, having the following 2 processes.

Plate manufacturing process

Embossing Process

On the other hand, since this process is directly applied to a resin material film to form a diffraction grating such as a hologram, an embossing process is not necessary in addition to the plate manufacturing process. As a result, the manufacturing cost is reduced.

Fig. 60 shows the information display medium 100 according to embodiments 1 to 9 of fig. 5, and shows a case where the information display medium 100 is formed with a continuous modified portion 521, a discontinuous modified portion 522, or a modified region 523 in the substrate 10, and an information display region 560 is formed by an interface 530 or

simulated interfaces

531 and 532 based on these portions. Diffracted light is optically generated by the interface 530 or the

simulated interfaces

531, 532, thereby displaying information in the information display area 560. In fig. 60, a case where the displayed information is "12345" of the digital information is shown.

Here, the displayed information may be not only a number but also other specific patterns. Other specific patterns refer to character information, patterns, symbols, geometric patterns, and the like.

Fig. 61 shows an information display medium 100 according to embodiment 10 of the present disclosure, in which the information display medium 100 includes a continuous modified portion 521, a discontinuous modified portion 522, or a modified region 523 formed inside a base material 10, an information display region 560 obtained by an interface 530 or a

simulation interface

531, 532 of the portion, a printed portion 570 formed by printing ink or the like on a surface of the base material 10, a continuous modified portion 521, a discontinuous modified portion 522, or a modified region 523 formed inside a base material 10A newly attached to the base material 10, and an information display region 561 obtained by the interface 530 or the

simulation interface

531, 532 of the portion.

In practice, the information display medium 100 may be obtained by attaching the portion in which the information display region 561 is formed inside the base material 10A to the base material 10 in advance, or the information display region 561 may be formed inside the base material 10A after the base material 10A is attached as described above.

As shown in fig. 61, the information display medium 100 may be formed using information other than the information display area 560. In addition, not only the information display area 560 may be formed in a single substrate 10, but also the information display area 561 may be formed in an additionally formed substrate 10A and information that has newly become visible may be recorded.

Further, the information display area 560 and the printing portion 570 may be overlapped.

Thus, the information display medium 100 can have a plurality of information formed in the printing portion 570, the information display area 560 formed in the base 10, and the information display area 561 formed in the base 10A.

(Effect and others)

An information display medium according to embodiment 5 is an information display medium having an information display region inside a base material made of a light-transmitting organic material, and is characterized in that a modified portion having a property different from that of other regions is continuously formed inside the base material so that a part or all of modified portions adjacent to each other inside the base material overlap each other, a continuous modified portion is provided so that an interface with a non-modified region is formed into a continuous curved surface shape, and information is displayed in the information display region in accordance with the curved surface shape.

Thus, the interface between the non-modified region and the continuously modified portion can be formed by a continuous curved surface shape, and the optical response can be modulated by the interface shape, whereby information can be recorded in the information display region inside the base material. Further, since the interface shape is formed inside the base material, when the display information is peeled off by forgery, or alteration, the display information is easily destroyed, and forgery, or alteration is difficult, and a higher forgery prevention effect can be exhibited.

An information display medium according to another aspect of embodiment 5 is an information display medium having an information display region inside a base material made of a light-transmissive organic material, and is characterized in that a modified portion having a property different from that of other regions is discontinuously formed inside the base material so that adjacent modified portions do not overlap with each other inside the base material, a discontinuous modified portion is provided in which a pseudo interface with an unmodified region is formed into a continuous curved surface shape, and information is displayed in the information display region in accordance with the curved surface shape.

In this way, a simulated interface between the non-modified region and the continuously modified portion can be formed by a continuous curved surface shape, and information can be recorded in the information display region inside the base material by modulating the optical response by the shape of the simulated interface. Further, since the shape of the pseudo interface is formed inside the base material, when the display information is peeled off by forgery, or alteration, the display information is easily destroyed, and forgery, or alteration is difficult, and a higher forgery prevention effect can be exhibited.

In the information display medium, it is preferable that at least 2 or more continuous modified portions are provided in the substrate.

In the information display medium, it is preferable that at least 2 or more discontinuous modified parts are provided in the substrate.

Thereby, a plurality of display information based on the optical response of the continuous modified portion or the discontinuous modified portion can be provided inside the base material.

In the information display medium, it is preferable that the curved surface is formed of a repeating pattern.

This can present the following optical effect and information.

In the information display medium, a fresnel-shaped specific free-form surface structure may be formed inside the base material by the curved surface shape, and the information may be displayed in the information display area by reflected light reflected by the fresnel-shaped specific free-form surface structure.

In the information display medium, the curved surface shape is preferably a curved surface shape represented by a periodic function. In the information display medium, the curved surface shape may be a curved surface shape represented by an overlap function including at least 2 periodic functions or more.

This can present the following optical effect and information.

In the information display medium, a diffraction grating structure may be formed in the curved surface shape, and the information may be displayed in the information display area by diffracted light diffracted by the diffraction grating structure.

In the information display medium, a volume hologram structure may be formed inside the base material by the curved surface shape, and the information may be displayed in the information display region by diffracted light diffracted by the volume hologram structure.

In the information display medium, a kinoform structure may be formed in the curved surface shape, and the information may be displayed in the information display area by diffracted light diffracted by the kinoform structure.

In the information display medium, a light scattering structure may be formed by the curved surface shape, and the information may be displayed in the information display area by using scattered light scattered by the light scattering structure.

A method for manufacturing an information display medium according to another aspect of embodiment 5 is a method for manufacturing an information display medium having an information display region inside a base material made of a light-transmitting organic material, and includes: a step of locally applying energy to the inside of the base material to form a modified portion having a property different from that of other regions in the energy application portion inside the base material; and a step of forming a continuous modified portion in which the modified portions are continuously formed so that a part or all of the modified portions adjacent to each other in the substrate overlap each other, and an interface with a non-modified region is formed into a continuous curved surface shape.

In the method for producing an information display medium, it is preferable that 1 continuous modified portion is formed inside the base material.

This makes it possible to form the curved surface shape by densely arranging the modified regions (continuous modified portions).

In the method for producing an information display medium, 2 or more continuous modified portions may be formed in the base material.

This makes it possible to arrange the reformed region (continuous reformed portion) densely and to increase the area of the region in which the reformed region is formed.

A method for manufacturing an information display medium according to another aspect of embodiment 5 is a method for manufacturing an information display medium having an information display region inside a base material made of a light-transmitting organic material, and includes: a step of locally applying energy to the inside of the base material to form a modified portion having a property different from that of other regions in the energy application portion inside the base material; and forming the non-continuous modified portion such that a pseudo interface between non-modified regions is formed into a continuous curved surface shape.

In the method of manufacturing an information display medium, it is preferable that 1 of the discontinuously modified parts is formed inside the base material.

This makes it possible to form the curved surface shape by densely arranging the reformed region (discontinuous reformed portion).

In the method for producing an information display medium, at least 2 or more continuous modified portions may be formed in the base material.

This makes it possible to arrange the reformed region densely (discontinuous reformed portion) and to increase the area of the region in which the reformed region is formed.

In the method for producing an information display medium, it is preferable that at least 2 or more modified portions are simultaneously formed in the base material.

This can shorten the process time for forming the modified region (continuous modified portion or discontinuous modified portion).

As described above, according to the information display medium and the method of manufacturing the same of the present embodiment, the information display region capable of improving the forgery prevention effect is formed inside the base material, and thus it is possible to provide an information display medium capable of exhibiting a higher forgery prevention effect.

The information display medium 100 according to the present disclosure can display a plurality of pieces of information in locally different regions when viewed in reflection, can be used as an optical effect for forgery prevention, and can be used as a forgery prevention medium for protecting value and information included in articles such as securities, certificates, brand goods, high-priced goods, electronic devices, and personal authentication media.

The information display medium 100 according to the present disclosure can be used for purposes other than forgery prevention, and can be used as, for example, toys, learning materials, ornaments for commodities, posters, and the like.

Examples

Specific examples of the present disclosure will be described below, but the present disclosure is not limited to this embodiment.

"example 1"

Aluminum is deposited on the plastic substrate as the light reflecting layer 20 to a thickness of about 50 nm.

Next, aluminum as the light reflecting layer 20 was partially removed by a femtosecond laser.

In the information display medium obtained as described above, although the metallic luster of aluminum can be confirmed in the reflection observation, the transmittance differs depending on the aluminum partially removed in the perspective observation, and the watermark pattern of aluminum can be confirmed.

"example 2"

(2 nd embodiment-1)

After forming a UV curable resin as a structure forming layer to a thickness of 2 μm on a PET film carrier substrate, the above-described structure was formed on the structure forming layer using a metal plate including a region of a 2-dimensional grating structure (1 st region) having a structure pitch of 300nm and a structure depth of 350nm, a region of a random dot structure (1 st region) having a structure pitch of 800nm and a structure depth of 200nm, and a region of a flat structure (2 nd region).

After the structure was formed as described above, aluminum was deposited as the light reflecting layer 20 to a film thickness of 50 nm. Then, the femtosecond laser was aimed at the PET film carrier substrate side so that the position with a thickness of 1 μm of the structure formation layer was at the focal position, and aluminum in the 2-dimensional grating structure region having a structure pitch of 300nm and a structure depth of 350nm was removed by scanning. Further, the line width of the area after the aluminum removal is 2 μm to 5 μm.

Further, the intensity of the femtosecond laser was increased at another position of the information display medium, and the irradiation was aimed from the PET film carrier substrate side so that the position where the thickness of the structure forming layer was 1 μm was a focal position, and aluminum in the irradiated region except for the region of the flat structure was removed by scanning. Further, the line width of the area after the aluminum removal is 2 μm to 5 μm.

Then, at another position of the information display medium, the irradiation region was scanned by aiming the femtosecond laser beam from the PET film carrier substrate side so that the position where the thickness of the structure forming layer was 1.5 μm was the focal position, thereby removing aluminum in the irradiation region. Further, the line width of the area after the aluminum removal is 2 μm to 5 μm.

In the information display medium obtained as described above, the region after the aluminum removal is covered with the 1 st information such as a pattern, a character, and a numeral formed by the 1 st region due to the excessively thin line width in the reflection observation, and it is difficult to visually confirm the formation in the perspective observation, while the region after the aluminum removal is improved in the transmittance in the perspective observation, and therefore, the identification information such as the watermark pattern can be visually confirmed by the region after the aluminum removal.

(2 nd embodiment-2)

After forming a UV curable resin as a structure forming layer to a thickness of 2 μm on a PET film carrier substrate, the structure was formed on the structure forming layer using a metal plate including a region of a 2-dimensional grating structure having a structure pitch of 300nm and a structure depth of 350nm, a region of a random dot structure having a structure pitch of 800nm and a structure depth of 200nm, and a region of a flat structure.

After the structure was formed, aluminum was deposited as the light reflecting layer 20 to a film thickness of 50 nm. Then, the irradiation with the femtosecond laser was aimed from the PET film carrier substrate side so that the position where the thickness of the structure forming layer was 1 μm was a focal position, and scanning was performed with a large width to remove aluminum in the irradiated region except for the region of the flat structure. Further, the line width of the area after the aluminum removal is 3mm or more.

Then, at another position of the information display medium, the irradiation region was scanned by aiming the femtosecond laser beam from the PET film carrier substrate side so that the position where the thickness of the structure forming layer was 1.5 μm was the focal position, thereby removing aluminum in the irradiation region. Further, the line width of the area after the aluminum removal is 2mm or more.

In the information display medium obtained as described above, the optical effect of the uneven structure cannot be visually confirmed with respect to the area after aluminum removal in the reflection observation. On the other hand, the optical effect can be visually confirmed in the region where aluminum remains. Further, by scanning the substrate with a large width, information formed by the area from which aluminum has been removed can be visually confirmed.

"example 3"

(example 3-1)

Optically variable inks are printed on a paper substrate.

Next, the paper substrate and the optically variable ink are partially removed by a pulsed laser.

In the information display medium obtained as described above, the processing of the paper base material cannot be visually observed at the time of reflection observation, and the processing of the optically variable ink can be visually observed, but the optical transmittance is different for the paper base materials which are partially removed and have different thicknesses at the time of perspective observation, and the watermark pattern can be visually confirmed.

(example 3-2)

The plastic base material is a carbonized part in which a space part forming a void is locally formed in the plastic base material by melting and sublimating a plastic by a pulse laser, and the plastic base material is carbonized.

In the information display medium obtained as described above, light is scattered in the void portion and absorbed in the carbonized part during reflection observation, but the amount of light absorbed by the carbonized part is large, and information can be observed according to the density of the carbonization. In the perspective observation, information different from that in the reflection observation is visually recognized according to the difference in the unit price shade and the degree of scattering of light in the void.

"example 4"

An acrylic resin-based UV-curable resin is applied to a plastic substrate as a structure-forming layer, and the UV-curing is performed by patterning the uneven structure into the UV-curable resin using a metal plate having an uneven structure formed thereon in advance. On the top, aluminum was deposited as a light reflecting layer to a thickness of about 50 nm.

Next, a solution of silver nitrate and polyvinylpyrrolidone dissolved in water was applied to aluminum, and dried to form a metal ion-containing layer. Then, silver fine particles having an average particle diameter of about 100nm are formed in the metal ion-containing layer by a femtosecond laser. And, aluminum is locally removed using the same femtosecond laser.

In the information display medium obtained as described above, it was possible to visually confirm that the metal ion containing layer was colored in yellow by the silver fine particles. In addition, in the region where aluminum overlaps with the colored region, a golden metallic luster is obtained. Further, light diffracted by the uneven structure can be visually confirmed.

"example 5"

(example 1)

The modified regions 523 are formed with a pitch of 1 μm inside the base material 10 by a pulsed laser.

In the information display medium 100 obtained as described above, the diffracted light can be visually confirmed by tilting the information display medium 100. In addition, the diffracted light can be visually confirmed even in the perspective observation.

(example 2)

The modified region 523 is provided inside the substrate 10 by a pulsed laser so that the substrate 10 is carbonized.

The information of the density of the charring can be visually confirmed. In addition, very weak diffracted light can be confirmed.

(example 3)

Inside the substrate 10 on which information has been formed at the lower interface of the substrate 10 with printing ink, the modified regions 523 are formed with a pitch of 1 μm with a pulsed laser.

In the information display medium 100 obtained as described above, the diffracted light can be visually confirmed by tilting the information display medium 100. In addition, the diffracted light can be visually confirmed even in the perspective observation. Further, the information on the printing ink formed on the lower interface of the substrate 10 can be confirmed without deterioration.

The present disclosure has been described above with reference to the embodiments, but the scope of the present disclosure is not limited to the illustrated embodiments, and includes all embodiments that can provide effects equivalent to the purpose of the present disclosure. The scope of the present disclosure is not limited to the combinations of the features of the invention defined by the claims, and can be defined by all combinations of specific features among all the disclosed features.

In addition, the entire contents of Japanese patent application laid-open No. 2016-.

Description of the reference numerals

10 base material (Structure forming layer)

20 light reflecting layer

21. 70 2 nd information display area

21a, 21b 2 nd information display area

30. 601 st zone

31. 61 region 2

50 laser

51 lens

52 laser source

53 mirror, half mirror

62 sub-region

62a, 62b, 62c, 62d sub-regions

100. 200 information display medium

260 authentication machine

261 image pickup device

330. 331, 332, 333 modified region

330. 370 application area

340. 341 information display area

Low reflection part of 411B light

412 metal ion containing layer

413 micro-particles

511 non-modified region

520 modified part

521. 521a, 521b continuous modified part

523 modified region

531. 532 simulation interface

560. 561 information display area

Claims

1. An information display medium characterized in that,

a light reflecting layer made of 1 or more kinds of materials selected from a metal, an alloy, a metal compound, and a semi-metal compound is disposed on one surface of a base material,

the light reflecting layer includes:

a 1 st region for displaying 1 st information having authentication information by one or a combination of an outer edge shape and a shape of the concave-convex region; and

a 2 nd information display region configured to display identification information in a shape in which a part or all of the 2 nd information display region overlaps with the light reflection layer in the 1 st region, the light reflection layer displaying the 1 st information, and a material of a part of the light reflection layer is removed,

the substrate has a structure forming layer having a concave-convex structure formed by a plurality of convex portions or concave portions on a surface corresponding to the 1 st region of the one surface, and a surface corresponding to the 2 nd region continuous to the 1 st region is flat or has a surface shape having a roughness smaller than that of the 1 st region,

the light reflecting layer is formed of 1 or more materials selected from metals, alloys, metal compounds, and semi-metal compounds having a refractive index different from that of the structure forming layer, on the surface of the structure forming layer corresponding to the 1 st region and the 2 nd region.

2. The information display medium according to claim 1,

the 2 nd information display area is set to span both the 1 st area and the 2 nd area.

3. The information display medium according to claim 1 or 2,

the width of a region obtained by removing a material from a part of the light reflection layer for displaying the identification information is a region width which can be formed by removing a material by irradiating a pulsed laser beam.

4. The information display medium according to claim 3,

the 1 st region is composed of 2 or more sub-regions adjacent to each other, and the amount of the material constituting the light reflection layer per unit area of 1 or more sub-regions among the sub-regions is reduced by 50% or more as compared with the amount of the material constituting the light reflection layer per unit area of the other sub-regions.

5. The information display medium according to claim 4,

the 1 st region includes: a 1 st sub-region in which the above-described uneven structure having an aspect ratio of 0.1 or more and less than 1 is formed; and a 2 nd sub-region having the above-described uneven structure with an aspect ratio of 1 or more and 2 or less,

the light reflection layer formed in the 2 nd sub-region has a material amount per unit area of the light reflection layer reduced by 50% or more as compared with the light reflection layer formed in the 1 st sub-region.

6. The information display medium according to claim 1 or 2,

the identification information obtained by removing a material locally on the light reflecting layer is formed by a material-removed portion or a material-remaining portion after the material removal.

7. The information display medium according to claim 1 or 2,

the 1 st information is composed of line drawings, handwriting, portrait drawings, landmarks, landscapes or a combination of the line drawings, the handwriting, the portrait drawings, the landmarks and the landscapes.

8. The information display medium according to claim 1 or 2,

the 1 st information is composed of geometric patterns, color stripes or a combination of the geometric patterns and the color stripes.

9. The information display medium according to claim 1 or 2,

the 1 st information includes a logo, a mark, a symbol, and an icon pattern.

10. The information display medium according to claim 1 or 2,

the identification information is recorded as a micro-engraved character.

11. A value document in which, in the case of,

the value document having embedded or bonded thereto the information display medium according to claim 1 or 2.

12. A method of verifying a valuable document according to claim 11,

the method of verification is characterized in that,

the authentication information of the information display medium is identified by reflected light or transmitted light,

the authentication information of the information display medium is identified by magnified observation of reflected light or transmitted light.

13. An identification information recording method for an information display medium, which is the identification information recording method for an information display medium according to claim 1 or 2,

the identification information recording method is characterized in that,

the light reflecting layer is partially removed by a pulsed laser beam to form the identification information.

14. An identification information recording method for an information display medium, which is the identification information recording method for an information display medium according to claim 1,

the identification information is formed by irradiating the inside of the structure forming layer with a pulsed laser beam condensed so that a region from a side where the light reflecting layer is not covered to an average thickness of the structure forming layer becomes a focal position, and removing the material.

15. An identification information recording method for an information display medium, which is the identification information recording method for an information display medium according to claim 1,

the identification information recording method is characterized in that,

the identification information is formed by irradiating the inside of the structure forming layer with a pulsed laser beam condensed so that a region from a side covered with the light reflecting layer to an average thickness of the structure forming layer becomes a focal position, and removing the material.

16. A method of manufacturing an information display medium,

there is the identification information recording method for an information display medium as set forth in claim 13.

17. A method for determining authenticity of an information display medium according to claim 1 or 2,

the authentication judging method is characterized in that,

the identification information is presented by irradiating a portion estimated to have the identification information of the information display medium with a pulsed laser beam.

18. The authentication method according to claim 17, wherein the authentication device further comprises a third module for determining whether the authentication device is authenticated,

the presented identification information is photographed by a photographing device, and authenticity is determined based on the photographed image.

19. A label, characterized in that it comprises, in a first aspect,

comprising:

the information display medium of any one of claims 1 to 10; and

and an adhesive layer formed on the back side of the information display medium.